diff --git a/CMakeLists.txt b/CMakeLists.txt
index 03b08b5f..eab33e0d 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -247,6 +247,7 @@ if(NOT TARGET clean_all)
     COMMAND ${CMAKE_BUILD_TOOL} clean
     COMMAND find . -name "*.o" -o -regex "./libsecutils[0-9-].*" | xargs rm
     COMMAND rm -rf debian/{tmp,libsecutils,libsecutils-dev,libsecutils-bin}
+    COMMAND rm -rf ${CMAKE_CURRENT_BINARY_DIR}/src/${PROJECT_NAME}.pc
     COMMAND find . -type d -name "build" | xargs -r rm -r
     # cowardly not doing rm -r ${CMAKE_BINARY_DIR}
 
diff --git a/README.md b/README.md
index 5f21baae..9cc92116 100644
--- a/README.md
+++ b/README.md
@@ -48,11 +48,11 @@ also on a virtual machine or the Windows Subsystem for Linux ([WSL](https://docs
 and with MacOS.
 
 The following network and development tools are needed or recommended.
-* Git (for getting the software, tested versions include 2.7.2, 2.11.0, 2.20, 2.34.1, 2.48.0)
-* CMake (for using [`CMakeLists.txt`](CMakeLists.txt), tested versions include 3.18.4, 3.22.1, 3.27.7, 3.31.5)
+* Git (for getting the software, tested versions include 2.7.2, 2.11.0, 2.20, 2.34.1, 2.48.0, 2.53.0)
+* CMake (for using [`CMakeLists.txt`](CMakeLists.txt), tested versions include 3.18.4, 3.22.1, 3.27.7, 3.31.5, 4.3.0)
 * GNU make (tested versions include 3.81, 4.1, 4.2.1, 4.3)
-* GNU C compiler (gcc, tested versions include 5.4.0, 7.3.0, 8.3.0, 10.2.1, 11.4.0, 12.2.0)
-  or clang (tested versions include 14.0.3, 17.0.3, 19.1.1)
+* GNU C compiler (gcc, tested versions include 5.4.0, 7.3.0, 8.3.0, 10.2.1, 11.4.0, 12.2.0, 13.3.0)
+  or clang (tested versions include 14.0.3, 17.0.3, 19.1.1, 22.1.1)
 
 The following OSS components are used.
 * OpenSSL development edition, at least version 3.0. Tested, among others,
diff --git a/src/libsecutils/include/secutils/certstatus/cdp_util.h b/src/libsecutils/include/secutils/certstatus/cdp_util.h
index 4be309e2..c34215ae 100644
--- a/src/libsecutils/include/secutils/certstatus/cdp_util.h
+++ b/src/libsecutils/include/secutils/certstatus/cdp_util.h
@@ -5,8 +5,6 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
-*
 * This work is licensed under the terms of the Apache Software License 
 * 2.0. See the COPYING file in the top-level directory.
 *
diff --git a/src/libsecutils/include/secutils/certstatus/crl_mgmt.h b/src/libsecutils/include/secutils/certstatus/crl_mgmt.h
index a68fc7c3..1eac35fa 100644
--- a/src/libsecutils/include/secutils/certstatus/crl_mgmt.h
+++ b/src/libsecutils/include/secutils/certstatus/crl_mgmt.h
@@ -5,8 +5,6 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
-*
 * This work is licensed under the terms of the Apache Software License 
 * 2.0. See the COPYING file in the top-level directory.
 *
diff --git a/src/libsecutils/include/secutils/certstatus/crls.h b/src/libsecutils/include/secutils/certstatus/crls.h
index b9ec53d7..3ac31e70 100644
--- a/src/libsecutils/include/secutils/certstatus/crls.h
+++ b/src/libsecutils/include/secutils/certstatus/crls.h
@@ -42,6 +42,7 @@ bool CRL_check(const char *src, OPTIONAL X509_CRL *crl, OPTIONAL const X509_VERI
  * @brief retrieve CRL in DER format (ASN.1) from given CRL distribution point
  *
  * @param url the location of the CDP
+ * @note when given an https URL, uses trivial unauthenticated TLS
  * @param timeout number of seconds the HTTP transaction may take, or 0 for infinite or -1 for default
  * @param max_resp_len the maximal size of the response message, or 0 for the OpenSSL default: 100 kiB
  * @param desc description of the CRL to use for any error messages, or null
@@ -65,6 +66,8 @@ int check_cert_crls(X509_STORE_CTX* ctx, OPTIONAL STACK_OF(X509_CRL) * crls, con
 
 /*!
  * @brief check the revocation status of the certificate at current error depth in ctx using CDPs
+ * @note This does not limit the use of URLs taken from CDP entries in the certificate.
+ * Thus any referenced online endpoints and local file locations may get accessed.
  *
  * @param ctx pointer to verification context structure including the cert to check
  * @return 1 on success, 0 on rejection (i.e., cert revoked), -2 on no CRL available, -1 on other error
diff --git a/src/libsecutils/include/secutils/certstatus/ocsp.h b/src/libsecutils/include/secutils/certstatus/ocsp.h
index 7cc164f4..fa500d80 100644
--- a/src/libsecutils/include/secutils/certstatus/ocsp.h
+++ b/src/libsecutils/include/secutils/certstatus/ocsp.h
@@ -32,6 +32,7 @@
  * @brief obtain OCSP response from given OCSP responder
  *
  * @param url the location of the OCSP responder
+ * @note when given an https URL, uses trivial unauthenticated TLS
  * @param timeout number of seconds the HTTP transaction may take, or 0 for infinite or -1 for default
  * @param req the OCSP request to send
  * @param desc description of contents to use for any error messages, or null
@@ -45,6 +46,7 @@ static const int OCSP_DEFAULT_TIMEOUT = 10; /* in seconds */
 /*!
  * @brief check cert status using the given OCSP response
  * @note the OCSP response may be obtained using an OCSP request or OCSP stapling
+ * @note at this level, any nonce and cert ID relating request and response cannot be checked
  *
  * @param ts pointer to trust store containing verification parameters
  * @param untrusted a stack of certs that may be used for chain building, or null
@@ -59,6 +61,10 @@ int check_ocsp_resp(X509_STORE* ts, STACK_OF(X509) *untrusted,
 /*!
  * @brief check cert revocation status via OCSP.
  * @note tries using any AIA entries (if enabled) then try any given fallback OCSP responder URLs, in the given order
+ * @note This does not limit the use of URLs taken from AIA entries in the certificate.
+ * Thus any referenced online endpoints and local file locations may get accessed.
+ * @note to avoid performance penalty on OCSP responders, does not use nonce for
+ * replay protection when retrieving OCSP response unless defined SECUTILS_OCSP_USE_NONCE
  *
  * @param ctx verification context containing verification parameters etc.
  * @param untrusted a stack of certs that may be used for chain building, or null
diff --git a/src/libsecutils/include/secutils/connections/http.h b/src/libsecutils/include/secutils/connections/http.h
index 1282cc1f..c95aadb7 100644
--- a/src/libsecutils/include/secutils/connections/http.h
+++ b/src/libsecutils/include/secutils/connections/http.h
@@ -26,6 +26,8 @@
  * @brief obtain ASN.1 response from given server
  *
  * @param url the location of the server
+ * @note when given an https URL, uses trivial unauthenticated TLS -
+ * so use with care; this is okay for retrieving CRLs and OCSP responses
  * @param timeout number of seconds the HTTP transaction may take, or 0 for infinite
  * @param max_resp_len the maximal size of the response message, or 0 for the default: 100k
  * @param content_type the content type of the request, or null
diff --git a/src/libsecutils/include/secutils/credentials/credentials.h b/src/libsecutils/include/secutils/credentials/credentials.h
index 578847ef..b88d51e9 100644
--- a/src/libsecutils/include/secutils/credentials/credentials.h
+++ b/src/libsecutils/include/secutils/credentials/credentials.h
@@ -153,7 +153,8 @@ void CREDENTIALS_free(OPTIONAL CREDENTIALS* creds);
 
 /*!*****************************************************************************
  * @brief load asymmetric credentials from the given file(s) and optionally crypto engine
- * @note If used, encryption indirectly also protects integrity&authenticity of file-based storage.
+ * @note If used, password-based decryption indirectly
+ * also checks integrity&authenticity of file-based storage.
  *
  * @param certs name of file holding certificate and optional chain, or null
  * @param key name of file holding private key or an engine key identifier, or null
@@ -173,9 +174,9 @@ CREDENTIALS* CREDENTIALS_load(OPTIONAL const char* certs, OPTIONAL const char* k
 
 
 /*!*****************************************************************************
- * @brief load asymmetric credentials from the given file(s) and optionally using DV-based integrity&authenticity
- *protection
- * @note If used, encryption indirectly also protects integrity&authenticity of file-based storage.
+ * @brief load asymmetric credentials from the given file(s),
+ * using DV-based decryption and integrity&authenticity check
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure password from DV
  *
  * @param certs name of file holding certificate and optional chain, or null
  * @param key name of file holding private key, or null
@@ -191,7 +192,8 @@ CREDENTIALS* CREDENTIALS_load_dv(OPTIONAL const char* certs, OPTIONAL const char
 
 /*!*****************************************************************************
  * @brief save asymmetric credentials (except key held in crypto engine or provider) to the given file(s)
- * @note If used, encryption indirectly also protects integrity&authenticity of file-based storage.
+ * @note If used, password-based encryption indirectly
+ * also protects integrity&authenticity of file-based storage.
  *
  * @param creds pointer to the credential structure to save
  * @param certs name of file to store certificates, or null. Any previous contents are overwritten.
@@ -214,8 +216,9 @@ bool CREDENTIALS_save(const CREDENTIALS* creds, OPTIONAL const char* certs, OPTI
 
 
 /*!*****************************************************************************
- * @brief save asymmetric credentials to the given file(s)
- * @note If used, encryption indirectly also protects integrity&authenticity of file-based storage.
+ * @brief save asymmetric credentials to the given file(s),
+ * using DV-based encryption and integrity&authenticity protection
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure password from DV
  *
  * @param creds pointer to the credential structure to save
  * @param certs name of file to store certificates, or null. Any previous contents are overwritten.
@@ -235,7 +238,7 @@ static const char* const CREDS_DIR_DEFAULT = "certs/creds";
 /*!*****************************************************************************
  * @brief obtain credentials of the given component (based on its ID) from PKCS#12 file
  * @note file name is derived from CREDS_DIR_ENV (defaulting to CREDS_DIR_DEFAULT), cid, and extension ".p12".
- * @note uses DV-based encryption, which also protects integrity&authenticity.
+ * @note does not use DV-based protection
  *
  * @param cid identifier of the component credentials
  * @return pointer to a new CREDENTIALS structure, or null on error
@@ -245,7 +248,7 @@ CREDENTIALS* CREDENTIALS_get(component_creds_id cid);
 /*!*****************************************************************************
  * @brief store credentials of the given component (based on its ID) in PKCS#12 format
  * @note file name is derived from CREDS_DIR_ENV (defaulting to CREDS_DIR_DEFAULT), cid, and extension ".p12".
- * @note uses DV-based encryption, which also protects integrity&authenticity.
+ * @note does not use DV-based protection
  *
  * @param cid identifier of the component credentials
  * @param creds credentials to store
diff --git a/src/libsecutils/include/secutils/credentials/store.h b/src/libsecutils/include/secutils/credentials/store.h
index 4d6f674e..6b92c07a 100644
--- a/src/libsecutils/include/secutils/credentials/store.h
+++ b/src/libsecutils/include/secutils/credentials/store.h
@@ -85,9 +85,13 @@ const char *STORE_get0_desc(OPTIONAL const X509_STORE *store);
  * @param stapling enable OCSP stapling, which makes sense only for TLS
  * @param crls (optional) provide a list of CRLS to be added to the store and enable CRL-based checks
  * @param use_CDP enable using HTTP CDP entries in certificates and enable CRL-based status checking
+ * @note The use of URLs taken from CDP entries in certificates is not limited.
+ * Thus any referenced online endpoints and local file locations may get accessed.
  * @param cdps (optional) provide fallback CDP URL(s) and enable CRL-based status checking
  * @param crls_timeout number of seconds fetching a CRL may take, or 0 for infinite or -1 for default (= 10)
  * @param use_AIA enable using AIA OCSP responder entries in certificates and enable OCSP-based status checking
+ * @note The use of URLs taken from AIA entries in certificates is not limited.
+ * Thus any referenced online endpoints and local file locations may get accessed.
  * @param ocsp (optional) provides fallback OCSP responder URL(s) and enable OCSP-based status checking
  * @param ocsp_timeout number of seconds getting an OCSP response may take, or 0 for infinite or -1 for default (= 10)
  * @return true on success, false on failure
@@ -135,6 +139,9 @@ X509_CRL *STORE_fetch_crl(const X509_STORE *store, OPTIONAL const char *url, int
 /*!
  * @brief create or extend cert store structure with any given cert(s)
  * @note sets CREDENTIALS_print_cert_verify_cb() enabling diagnostic log output
+ * @note This turns X509_V_ERR_CERT_NOT_YET_VALID into just a warning,
+ * effectively accepting not yet valid certificates, which are considered OK here.
+ *
  * @note use in addition STORE_set_parameters() to enable certificate status checks
  *
  * @param store certificate store to be extended if not null
@@ -157,6 +164,7 @@ X509_STORE* STORE_create(OPTIONAL X509_STORE* store, OPTIONAL const X509* cert,
  * @param vpm verification parameters, or null, governing if and how to check cert times,
  * depending on X509_V_FLAG_USE_CHECK_TIME and X509_V_FLAG_NO_CHECK_TIME
  * @param ctx (optional) pointer to UTA context for checking file integrity&authenticity using ICV
+ * @note if ctx is null or SECUTILS_USE_ICV not defined, no ICV-based check is done
  * @return true on success, false on error
  * @note For loaded certs their validity period and their CA flag are checked.
  *       Failures are logged as a warning if vpm is null, otherwise as an error.
@@ -177,6 +185,7 @@ bool STORE_load_more_check(X509_STORE** pstore, const char* file,
  * @param vpm verification parameters, or null, governing if and how to check cert times,
  * depending on X509_V_FLAG_USE_CHECK_TIME and X509_V_FLAG_NO_CHECK_TIME
  * @param ctx (optional) pointer to UTA context for checking file integrity&authenticity using ICV
+ * @note if ctx is null or SECUTILS_USE_ICV not defined, no ICV-based check is done
  * @return pointer to a new X509_STORE structure, or null on error
  * @note For loaded certs their validity period and their CA flag are checked.
  *       Failures are logged as a warning if vpm is null, otherwise as an error.
@@ -198,6 +207,7 @@ X509_STORE* STORE_load_check(const char* files, OPTIONAL const char* desc,
  * @param vpm verification parameters, or null, governing if and how to check cert times,
  * depending on X509_V_FLAG_USE_CHECK_TIME and X509_V_FLAG_NO_CHECK_TIME
  * @param ctx (optional) pointer to UTA context for checking file integrity&authenticity using ICV
+ * @note if ctx is null or SECUTILS_USE_ICV not defined, no ICV-based check is done
  * @note at least one valid certificate file must be found in all tested directories
  * @return true on success, false on error/failure
  * @note For loaded certs their validity period and their CA flag are checked.
@@ -217,7 +227,8 @@ bool STORE_load_check_dir(X509_STORE** pstore, const char* trust_dir,
  * @param crl_dir     directory where to search for CRLs
  * @param desc        description of CRLs to use for error reporting, or null
  * @param recursive   if true, use recursive search in subdirectories
- * @param ctx pointer to UTA context for checking file integrity&authenticity using ICV, or null
+ * @param ctx (optional) pointer to UTA context for checking file integrity&authenticity using ICV
+ * @note if ctx is null or SECUTILS_USE_ICV not defined, no ICV-based check is done
  * @note at least one valid CRL file must be found in each visited directory
  * @return true on success, false on error/failure
  ******************************************************************************/
diff --git a/src/libsecutils/include/secutils/credentials/trusted.h b/src/libsecutils/include/secutils/credentials/trusted.h
index 673b23c0..74d1ba56 100644
--- a/src/libsecutils/include/secutils/credentials/trusted.h
+++ b/src/libsecutils/include/secutils/credentials/trusted.h
@@ -37,6 +37,7 @@ static const char* const TRUST_CONFIG_ENTRY_CRLS = "crls";
  * @param cid identifier of the component, which indicates the config file section to use, or TRUST_CONFIG_SECTION_DEFAULT if it is 0
  * @param vpm OpenSSL certificate verification parameters to be taken over, or null for default
  * @param ctx (optional) pointer to UTA context for checking file integrity&authenticity using ICV
+ * @note if ctx is null or SECUTILS_USE_ICV not defined, no ICV-based check is done
  * @return pointer to a new CREDENTIALS structure, or null on error
  *******************************************************************************/
 X509_STORE* CREDENTIALS_get_trust_store(component_creds_id cid, OPTIONAL X509_VERIFY_PARAM* vpm, OPTIONAL uta_ctx* ctx);
diff --git a/src/libsecutils/include/secutils/credentials/verify.h b/src/libsecutils/include/secutils/credentials/verify.h
index 8fda3003..5c86094c 100644
--- a/src/libsecutils/include/secutils/credentials/verify.h
+++ b/src/libsecutils/include/secutils/credentials/verify.h
@@ -46,6 +46,9 @@ bool STORE_CTX_tls_active(const X509_STORE_CTX* ctx);
  * @param ctx_x509 pointer to structure containing certificate verification options like trusted certs
  * @return 0 if and only if the cert verification is considered failed
  *
+ * @note This callback turns X509_V_ERR_CERT_NOT_YET_VALID into just a warning,
+ * effectively accepting not yet valid certificates, which are considered OK here.
+ *
  * @note OpenSSL's X509_verify_cert function calls this function
  * during certificate verification whenever a problem has been
  * found and on success at the end of the verification to give an opportunity
@@ -78,6 +81,9 @@ bool verify_cb_cert(X509_STORE_CTX* store_ctx, X509* cert, int err);
  * @param cert certificate to be verified
  * @param untrusted (optional) intermediate certs that may be useful for building
  * the chain of certificates between the cert and the trusted certs in the trust store
+ * @note This function turns X509_V_ERR_CERT_NOT_YET_VALID into just a warning,
+ * effectively accepting not yet valid certificates, which are considered OK here.
+ *
  * @param trust_store pointer to structure containing trusted (root) certs and further verification parameters
  * @note trust_store may contain CRLs loaded via STORE_load_crl_dir()
  * @return < 0 on on verification error, 0 for invalid cert, 1 for valid cert
diff --git a/src/libsecutils/include/secutils/crypto/crypto.h b/src/libsecutils/include/secutils/crypto/crypto.h
index ad60724e..95aea653 100644
--- a/src/libsecutils/include/secutils/crypto/crypto.h
+++ b/src/libsecutils/include/secutils/crypto/crypto.h
@@ -5,7 +5,7 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
+* @author Martin Vitek <martin.vitek@siemens.com>
 *
 * This work is licensed under the terms of the Apache Software License 
 * 2.0. See the COPYING file in the top-level directory.
@@ -78,11 +78,11 @@ ssize_t AESGCM_decrypt(EVP_CIPHER_CTX* osslctx, uint8_t* plain_buff, size_t plai
 
 
 /*!
- * @brief The function finalizes encryption and store tag (integrity protection value).
+ * @brief The function finalizes encryption and stores tag (integrity protection value).
  *
- * @param osslctx pointer to context of decryption operation
+ * @param osslctx pointer to context of encryption operation
  * @param tag_buff     pointer to buffer used to store tag
- * @param tag_len      size of resulting tag to be stored in tag_buff
+ * @param tag_len      size of resulting tag to be stored in tag_buff, should be EVP_GCM_TLS_TAG_LEN
  * @note  If tag_buff is set to null and tag_len is set to 0 then tag will not be generated
  *
  * @return  true  on success
@@ -96,7 +96,7 @@ bool AESGCM_encrypt_final(EVP_CIPHER_CTX* osslctx, uint8_t* tag_buff, size_t tag
  *
  * @param osslctx pointer to context of decryption operation
  * @param tag     pointer to tag
- * @param tag_len size of tag
+ * @param tag_len size of tag, should be EVP_GCM_TLS_TAG_LEN
  * @note  If tag_buff is set to null and tag_len is set 0 then authenticity will not be checked
  * @param plain   pointer to plain text obtained by calling AESGCM_decrypt or null
  * @note  on failure the function cleans plain text if parameter plain is not null
diff --git a/src/libsecutils/include/secutils/operators.h b/src/libsecutils/include/secutils/operators.h
index f8c9d985..8d45d89c 100644
--- a/src/libsecutils/include/secutils/operators.h
+++ b/src/libsecutils/include/secutils/operators.h
@@ -5,7 +5,7 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
+* @author Martin Barta <martin.barta@siemens.com>
 *
 * This work is  licensed under the terms of the Apache Software License 
 * 2.0. See the COPYING file in the top-level directory.
diff --git a/src/libsecutils/include/secutils/storage/files_dv.h b/src/libsecutils/include/secutils/storage/files_dv.h
index bf875420..8f9f4cae 100644
--- a/src/libsecutils/include/secutils/storage/files_dv.h
+++ b/src/libsecutils/include/secutils/storage/files_dv.h
@@ -31,6 +31,7 @@
 
 /*!
  * @brief get file encryption password from UTA using derivation value based on file path name
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure password
  *
  * @param pass_buf place to store the derived password as base64 encoded string, must be at least MAX_UTA_PASS_LEN chars
  * long
@@ -55,6 +56,7 @@ bool FILES_get_dv(const char* filename, unsigned char* dv_out);
 
 /*!
  * @brief store private key in given file and format, optionally using DV-based password
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure password from DV
  *
  * @param pkey private key to save
  * @param file (path) name of the output file. Any previous contents are overwritten.
@@ -70,6 +72,7 @@ bool FILES_store_key_dv(const EVP_PKEY* pkey, const char* file, file_format_t fo
 
 /*!
  * @brief load private key from the given file or engine with flexible format, optionally using DV-based password
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure password from DV
  *
  * @param key file (path) name of the input file or engine key ID
  * @param file_format the format to try first when reading file contents
@@ -85,6 +88,7 @@ EVP_PKEY* FILES_load_key_autofmt_dv(OPTIONAL const char* key, file_format_t file
 
 /*!
  * @brief load certificates from the given file with flexible format, optionally using DV-based password
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure password from DV
  *
  * @param file (path) name of the input file
  * @param format the format to try first when reading file contents
diff --git a/src/libsecutils/include/secutils/storage/files_icv.h b/src/libsecutils/include/secutils/storage/files_icv.h
index bf278e50..e43e2ea9 100644
--- a/src/libsecutils/include/secutils/storage/files_icv.h
+++ b/src/libsecutils/include/secutils/storage/files_icv.h
@@ -26,6 +26,7 @@
 /*!
  * @brief (re-)protect integrity of file (of any type that allows appending text) with ICV derived via UTA
  *        from the absolute path name of the file
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param file (path) name of the file to be protected
@@ -37,6 +38,7 @@ bool FILES_protect_icv(OPTIONAL uta_ctx* ctx, const char* file);
 /*!
  * @brief (re-)protect integrity of file (of any type that allows appending text) with ICV derived via UTA
  *        from the supplied path name of the file. If none is supplied, the absolute path is derived.
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param file (path) name of the file to be protected
@@ -49,6 +51,7 @@ bool FILES_protect_icv_at(OPTIONAL uta_ctx* ctx, const char* file, const char* l
 /*!
  * @brief (re-)protect integrity of file, if it has suffix .pem, .crt, or .cnf (unless SECUTILS_NO_ICV), with ICV
  * derived via UTA
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param file (path) name of the file to be protected
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
@@ -60,6 +63,7 @@ bool FILES_protect_icv_config_trusted(const char* file, OPTIONAL uta_ctx* ctx);
 /*!
  * @brief check integrity of file (of any type that allows appending text) using ICV derived via UTA
  *        from the absolute path name of the file
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param file (path) name of the file to be checked
@@ -71,6 +75,7 @@ bool FILES_check_icv(OPTIONAL uta_ctx* ctx, const char* file);
 /*!
  * @brief check integrity of file (of any type that allows appending text) using ICV derived via UTA
  *        from the supplied path name of the file. If none is supplied, the absolute path is derived.
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param file (path) name of the file to be checked
@@ -82,6 +87,7 @@ bool FILES_check_icv_at(OPTIONAL uta_ctx* ctx, const char* file, const char* loc
 
 /*!
  * @brief load a certificate from the given PEM file, checking ICV-based protection
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param file (path) name of the input file
@@ -93,6 +99,7 @@ X509* FILES_load_cert_pem_icv(OPTIONAL uta_ctx* ctx, const char* file, OPTIONAL
 
 /*!
  * @brief store the given certificate in given PEM file, with ICV-based protection
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param cert certificate to save
@@ -105,6 +112,7 @@ bool FILES_store_cert_pem_icv(OPTIONAL uta_ctx* ctx, const X509* cert, const cha
 
 /*!
  * @brief store the given certificate in given PEM file and optionally add ICV-based protection
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param cert certificate to save
@@ -119,6 +127,7 @@ bool FILES_store_cert_pem(OPTIONAL uta_ctx* ctx, const X509* cert, const char* f
 
 /*!
  * @brief store the given CRL in given PEM file, with ICV-based protection
+ * @note If SECUTILS_USE_UTA is not set, cannot derive secure ICV
  *
  * @param ctx pointer to UTA context, which typically is part of the libsecutils context, or null
  * @param crl CRL to save
diff --git a/src/libsecutils/include/secutils/util/util.h b/src/libsecutils/include/secutils/util/util.h
index 5db947e4..2be7a343 100644
--- a/src/libsecutils/include/secutils/util/util.h
+++ b/src/libsecutils/include/secutils/util/util.h
@@ -359,7 +359,7 @@ bool UTIL_get_random(void *buf, size_t len);
  *        is needed for the copied string. If the size_needed is null the size is not returned.
  *
  * @return number of bytes excluding the terminating NUL that have been copied to destination,
- *         -1 on error, e.g., the source is null or
+ *         -1 on error, e.g., the source is null or the length is > INT_MAX or
  *            the destination is not null and the buffer size is 0.
  */
 int UTIL_safe_string_copy(const char *source, OPTIONAL char *destination,
diff --git a/src/libsecutils/src/certstatus/cdp_util.c b/src/libsecutils/src/certstatus/cdp_util.c
index 490ab040..2c57a8eb 100644
--- a/src/libsecutils/src/certstatus/cdp_util.c
+++ b/src/libsecutils/src/certstatus/cdp_util.c
@@ -5,8 +5,6 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
-*
 * This work is licensed under the terms of the Apache Software License
 * 2.0. See the COPYING file in the top-level directory.
 *
@@ -85,10 +83,14 @@ const char *CDP_get_uri_from_general_names(
            protocol prefixes, the distribution point has been found
         */
         uri = GENERAL_NAME_get0_value(name_entry, &gtype);
-        if(gtype == GEN_URI && ASN1_STRING_length(uri) > 7)
-        {
-            /* uri is of type ASN1_STRING */
+        if (gtype == GEN_URI) {
             const char *asn1_uri = (const char *)ASN1_STRING_get0_data(uri);
+            int len = ASN1_STRING_length(uri);
+
+            if (asn1_uri == NULL || len <= 6 || memchr(asn1_uri, '\0', (size_t)len) != NULL) {
+                LOG(FL_WARN, "ignoring CDP URI that is invalid, too short, or has embedded NUL byte");
+                continue;
+            }
             if (CONN_IS_HTTP(asn1_uri) || CONN_IS_HTTPS(asn1_uri))
             {
                 return asn1_uri;
diff --git a/src/libsecutils/src/certstatus/crl_mgmt.c b/src/libsecutils/src/certstatus/crl_mgmt.c
index 88b859e0..5d74666b 100644
--- a/src/libsecutils/src/certstatus/crl_mgmt.c
+++ b/src/libsecutils/src/certstatus/crl_mgmt.c
@@ -5,8 +5,6 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
-*
 * This work is licensed under the terms of the Apache Software License
 * 2.0. See the COPYING file in the top-level directory.
 *
@@ -128,17 +126,19 @@ static X509_CRL *get_crl_from_cache(const char * cachefile)
         ASN1_TIME *now = ASN1_TIME_new();
         ASN1_TIME_set(now, time(NULL));
         const ASN1_TIME *lastUpdate = X509_CRL_get0_lastUpdate(crl);
-        const ASN1_TIME *nextUpdate = X509_CRL_get0_nextUpdate(crl);
+        const ASN1_TIME *nextUpdate = X509_CRL_get0_nextUpdate(crl); /* may be NULL */
 
         CDP_get_x509_time(now, time_buf, sizeof(time_buf));
         LOG(FL_TRACE, "current time: %s", time_buf);
         CDP_get_x509_time(lastUpdate, time_buf, sizeof(time_buf));
         LOG(FL_TRACE, "CRL lastUpdate: %s", time_buf);
-        CDP_get_x509_time(nextUpdate, time_buf, sizeof(time_buf));
-        LOG(FL_TRACE, "CRL nextUpdate: %s", time_buf);
+        if (nextUpdate != NULL) {
+            CDP_get_x509_time(nextUpdate, time_buf, sizeof(time_buf));
+            LOG(FL_TRACE, "CRL nextUpdate: %s", time_buf);
+        }
 
         int isBeforeStart = ASN1_TIME_compare(now, lastUpdate) < 0;
-        int isAfterEnd = ASN1_TIME_compare(nextUpdate, now) <= 0;
+        int isAfterEnd = nextUpdate != NULL && ASN1_TIME_compare(nextUpdate, now) <= 0;
         int isAfterPublish = 0;
 
         int nextPublishIdx = X509_CRL_get_ext_by_NID(crl, NID_crl_next_publish, 0);
@@ -152,7 +152,15 @@ static X509_CRL *get_crl_from_cache(const char * cachefile)
 #if OPENSSL_VERSION_NUMBER < 0x10101000L
                 LOG(FL_ERR, "CRL nextPublish extension is present, but ASN1_TIME_set_string_X509 is not supported for OpenSSL version <1.1, sorry");
 #else
-                const char *nextPublishString = (const char*)ASN1_STRING_get0_data(data);
+                const char *nextPublishString = (const char *)ASN1_STRING_get0_data(data);
+                int len = ASN1_STRING_length(data);
+
+                if (nextPublishString == NULL || len <= 0
+                    || memchr(nextPublishString, '\0', (size_t)len) != NULL) {
+                    LOG(FL_WARN, "ignoring nextPublishString that is invalid or has embedded NUL byte");
+                    goto ignore;
+                }
+
                 while (*nextPublishString && !((*nextPublishString) & 0xE0)) {
                     ++nextPublishString;
                 }
@@ -165,6 +173,7 @@ static X509_CRL *get_crl_from_cache(const char * cachefile)
                     LOG(FL_ERR, "CRL nextPublish extension is present, but time cannot be determined");
                 }
                 ASN1_TIME_free(nextPublish);
+            ignore: ;
 #endif
             }
         }
@@ -232,7 +241,8 @@ static X509_CRL *get_crl_by_download_or_from_cache(const CRLMGMT_DATA *data,
     }
 
     crl = CONN_load_crl_http(url, timeout, data->max_download_size, desc);
-    if (usecache && crl != NULL) {
+    if (usecache && crl != NULL
+        && X509_CRL_get0_nextUpdate(crl) != NULL /* otherwise would not know when to remove it again */) {
         put_crl_into_cache(crl, cachefile);
     }
     return crl;
diff --git a/src/libsecutils/src/certstatus/crls.c b/src/libsecutils/src/certstatus/crls.c
index 171b7865..a1cacd1f 100644
--- a/src/libsecutils/src/certstatus/crls.c
+++ b/src/libsecutils/src/certstatus/crls.c
@@ -297,9 +297,14 @@ static const char* get_dp_url(DIST_POINT* dp)
     {
         gen = sk_GENERAL_NAME_value(gens, i);
         uri = GENERAL_NAME_get0_value(gen, &gtype);
-        if(gtype is_eq GEN_URI and ASN1_STRING_length(uri) > 6)
-        {
-            char* uptr = (char*)ASN1_STRING_get0_data(uri);
+        if (gtype is_eq GEN_URI) {
+            const char *uptr = (const char *)ASN1_STRING_get0_data(uri);
+            int len = ASN1_STRING_length(uri);
+
+            if (uptr == NULL || len <= 6 || memchr(uptr, '\0', (size_t)len) != NULL) {
+                LOG(FL_WARN, "ignoring CDP URI that is invalid, too short, or has embedded NUL byte");
+                continue;
+            }
             if (CONN_IS_HTTP(uptr) || HAS_CASE_PREFIX(uptr, "file:"))
             {
                 return uptr;
@@ -381,15 +386,16 @@ int check_cert_status_cdps(X509_STORE_CTX* ctx)
     int n_delta = sk_DIST_POINT_num(delta_crldp);
     STACK_OF(DIST_POINT) *crldp =
         use_CDP ? X509_get_ext_d2i(cert, NID_crl_distribution_points, 0, 0) : 0;
+    int n_base = sk_DIST_POINT_num(crldp);
     char* fallback_urls = OPENSSL_strdup(cdps->urls);
     int timeout = cdps->timeout;
     int i;
     int res = -2; /* no CRL available, thus inconclusive */
 
     (void)ERR_set_mark();
-    if(n_delta <= 0 and sk_DIST_POINT_num(crldp) <= 0)
+    if(n_base <= 0 and n_delta <= 0)
     {
-        LOG(FL_DEBUG, use_CDP ? "no HTTP CDP in cert" : "cert CDP use is disabled");
+        LOG(FL_DEBUG, use_CDP ? "no CDP for base or delta CRLs in cert" : "cert CDP use is disabled");
     }
 
     /* Try downloading any delta CRL */
@@ -397,7 +403,7 @@ int check_cert_status_cdps(X509_STORE_CTX* ctx)
     X509_CRL* delta_crl = 0;
     for(i = 0; delta_crl is_eq 0 and i < n_delta; i++)
     {
-        const char* url = get_dp_url(sk_DIST_POINT_value(crldp, i));
+        const char* url = get_dp_url(sk_DIST_POINT_value(delta_crldp, i));
         if(url not_eq 0)
         {
             LOG(FL_DEBUG, "trying to load delta CRL from CDP URL:", url);
@@ -414,7 +420,7 @@ int check_cert_status_cdps(X509_STORE_CTX* ctx)
 
     /* Try downloading any base CRL */
     /* TODO sufficient to use the first CRL found ? */
-    for(i = 0; res < 0 and i < sk_DIST_POINT_num(crldp); i++)
+    for(i = 0; res < 0 and i < n_base; i++)
     {
         res = try_cdp(ctx, timeout, cert, get_dp_url(sk_DIST_POINT_value(crldp, i)),
                       0, delta_crl, nonfinal, "HTTP CDP entry in certificate");
diff --git a/src/libsecutils/src/certstatus/ocsp.c b/src/libsecutils/src/certstatus/ocsp.c
index cb92532d..5c79d332 100644
--- a/src/libsecutils/src/certstatus/ocsp.c
+++ b/src/libsecutils/src/certstatus/ocsp.c
@@ -185,7 +185,6 @@ static OCSP_RESPONSE* get_ocsp_resp(X509* cert, X509* issuer,
 {
     OCSP_REQUEST* req = 0;
     OCSP_CERTID* id_copy, *id = 0;
-    int res;
     OCSP_RESPONSE* resp = 0;
     OCSP_BASICRESP* br = 0;
     int i;
@@ -203,10 +202,12 @@ static OCSP_RESPONSE* get_ocsp_resp(X509* cert, X509* issuer,
         goto end;
     }
     id = 0;
+#ifdef SECUTILS_OCSP_USE_NONCE
     if(not OCSP_request_add1_nonce(req, 0, -1))
     {
         goto end;
     }
+#endif
 
     /* Add any extensions to the request */
     for(i = 0; i < sk_X509_EXTENSION_num(exts); i++)
@@ -228,18 +229,23 @@ static OCSP_RESPONSE* get_ocsp_resp(X509* cert, X509* issuer,
     if((br = OCSP_response_get1_basic(resp)) is_eq 0)
     {
         LOG(FL_ERR, "error getting OCSP basic response");
-        goto end;
+        goto err;
     }
+#ifdef SECUTILS_OCSP_USE_NONCE
+    int res;
     if((res = OCSP_check_nonce(req, br)) <= 0)
     {
         LOG(FL_ERR, res is_eq -1 ? "no nonce in OCSP response" : "nonce verification error");
-        goto end;
+        goto err;
     }
-    if(not OCSP_resp_find_status(br, id_copy, 0, 0, 0, 0, 0))
-    {
-        LOG(FL_ERR, "no OCSP status found matching cert ID in request");
+#endif
+    if (OCSP_resp_find_status(br, id_copy, 0, 0, 0, 0, 0))
         goto end;
-    }
+    LOG(FL_ERR, "no OCSP status found matching cert ID in request");
+
+ err:
+    OCSP_RESPONSE_free(resp);
+    resp = NULL;
 
  end:
     OCSP_CERTID_free(id);
diff --git a/src/libsecutils/src/config/config.c b/src/libsecutils/src/config/config.c
index 7e122f2c..58a43460 100644
--- a/src/libsecutils/src/config/config.c
+++ b/src/libsecutils/src/config/config.c
@@ -60,6 +60,8 @@ CONF* CONF_load_config(OPTIONAL ossl_unused uta_ctx* ctx, const char* file)
     if(0 not_eq file
 #ifdef SECUTILS_USE_ICV
        and FILES_check_icv(ctx, file) not_eq 0
+#else
+       and (ctx == NULL || (LOG(FL_ERR, "SECUTILS_USE_ICV not defined but UTA ctx is set"), false))
 #endif
       )
     {
diff --git a/src/libsecutils/src/connections/http.c b/src/libsecutils/src/connections/http.c
index 179a17a0..cf98ec7f 100644
--- a/src/libsecutils/src/connections/http.c
+++ b/src/libsecutils/src/connections/http.c
@@ -230,6 +230,7 @@ ASN1_VALUE* CONN_load_ASN1_http(const char* url, int req_timeout,
             LOG(FL_ERR, "error attaching trivial SSL context");
             goto err;
         }
+        LOG(FL_WARN, "using trivial unauthenticated TLS for downloading %s via %s", desc, url);
 # else
         LOG(FL_ERR, "TLS is not enabled in this build");
         goto err;
diff --git a/src/libsecutils/src/connections/tls.c b/src/libsecutils/src/connections/tls.c
index cb205a53..f8e3433d 100644
--- a/src/libsecutils/src/connections/tls.c
+++ b/src/libsecutils/src/connections/tls.c
@@ -320,6 +320,7 @@ SSL* TLS_connect(SSL_CTX* ctx, const char* host, OPTIONAL const char* port, int
     }
     /* link it with BIO connection */
     SSL_set_bio(ssl, conn, conn);
+    conn = NULL; /* as ownership has been transferred */
 
     if(not CONN_IS_IP_ADDR(hostaddr)
        and not SSL_set_tlsext_host_name(ssl, hostaddr))
@@ -336,7 +337,7 @@ SSL* TLS_connect(SSL_CTX* ctx, const char* host, OPTIONAL const char* port, int
 
 err:
     OPENSSL_free(host_str);
-    /* release the intermediate connection structure */
+    /* release the connection structure (unless ownership transferred to ssl) */
     CONN_free(conn);
     /* on error, release the SSL/TLS structure */
     if(0 is_eq res)
diff --git a/src/libsecutils/src/credentials/store.c b/src/libsecutils/src/credentials/store.c
index 5d79e20c..ef0d03cc 100644
--- a/src/libsecutils/src/credentials/store.c
+++ b/src/libsecutils/src/credentials/store.c
@@ -234,6 +234,12 @@ bool STORE_load_more_check(X509_STORE** pstore, const char* file,
         LOG_err("null pointer argument");
         goto err;
     }
+#ifndef SECUTILS_USE_ICV
+    if (ctx != NULL) {
+        LOG(FL_ERR, "SECUTILS_USE_ICV not defined but UTA ctx is set");
+        return false;
+    }
+#endif
 
 #ifdef DEBUG
     LOG(FL_DEBUG, "Loading %s from file '%s'", desc not_eq 0 ? desc : "?", file);
@@ -398,6 +404,12 @@ bool STORE_load_crl_dir(X509_STORE* pstore, const char* crl_dir, OPTIONAL const
         LOG(FL_ERR, "null pointer argument");
         goto err;
     }
+#ifndef SECUTILS_USE_ICV
+    if (ctx != NULL) {
+        LOG(FL_ERR, "SECUTILS_USE_ICV not defined but UTA ctx is set");
+        return false;
+    }
+#endif
 
     p_dir = opendir(crl_dir);
     if(0 is_eq p_dir)
diff --git a/src/libsecutils/src/crypto/crypto.c b/src/libsecutils/src/crypto/crypto.c
index 4b326d20..b8b5d753 100644
--- a/src/libsecutils/src/crypto/crypto.c
+++ b/src/libsecutils/src/crypto/crypto.c
@@ -5,7 +5,7 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
+* @author Martin Vitek <martin.vitek@siemens.com>
 *
 * This work is licensed under the terms of the Apache Software License 
 * 2.0. See the COPYING file in the top-level directory.
@@ -93,8 +93,27 @@ ssize_t AESGCM_encrypt(EVP_CIPHER_CTX* osslctx, uint8_t* cipher_buff, size_t cip
         return ret;
     }
 
-    int cipher_len = cipher_buff_len;
-    if((EVP_EncryptUpdate(osslctx, cipher_buff, &cipher_len, plain, plain_len) not_eq 1) or ((size_t)cipher_len not_eq plain_len))
+    if (cipher_buff_len > INT_MAX) {
+        LOG(FL_ERR, "cipher_buff_len > INT_MAX");
+        return ret;
+    }
+    if (plain_len > INT_MAX) {
+        LOG(FL_ERR, "plain_len > INT_MAX");
+        return ret;
+    }
+    int cipher_len = (int)cipher_buff_len;
+    int block_size = EVP_CIPHER_CTX_get_block_size(osslctx);
+    if (block_size <= 0) {
+        LOG(FL_ERR, "invalid cipher context (block size: %s)", block_size);
+        return ret;
+    }
+    int padding_len = (block_size - ((int)plain_len % block_size)) % block_size;
+    if ((int)plain_len > cipher_len - padding_len) {
+        LOG(FL_ERR, "cipher_buff_len = %zu too small, should be at least plain_len + padding_len = %zu",
+            cipher_buff_len, plain_len + padding_len);
+        return ret;
+    }
+    if((EVP_EncryptUpdate(osslctx, cipher_buff, &cipher_len, plain, (int)plain_len) not_eq 1) or ((size_t)cipher_len not_eq plain_len))
     {/* The second condition - GCM is used, hence length(plain_text) == length(cipher_text) */
         LOG(FL_ERR, "Encryption failed");
         return ret;
@@ -117,8 +136,22 @@ ssize_t AESGCM_decrypt(EVP_CIPHER_CTX* osslctx, uint8_t* plain_buff, size_t plai
         return ret;
     }
 
-    int plain_len = plain_buff_len;
-    if((EVP_DecryptUpdate(osslctx, plain_buff, &plain_len, cipher, cipher_len) not_eq 1)
+    if (plain_buff_len > INT_MAX) {
+        LOG(FL_ERR, "plain_buff_len > INT_MAX");
+        return ret;
+    }
+    if (cipher_len > INT_MAX) {
+        LOG(FL_ERR, "cipher_len > INT_MAX");
+        return ret;
+    }
+    if (plain_buff_len < cipher_len) {
+        LOG(FL_ERR, "plain_buff_len = %zu too small, should be at least cipher_len = %zu",
+            plain_buff_len, cipher_len);
+        return ret;
+    }
+
+    int plain_len = (int)plain_buff_len;
+    if((EVP_DecryptUpdate(osslctx, plain_buff, &plain_len, cipher, (int)cipher_len) not_eq 1)
        or ((size_t)plain_len not_eq cipher_len))
     {/* The second condition - GCM is used hence length(plain_text) == length(cipher_text) */
         LOG(FL_ERR, "Decryption failed");
diff --git a/src/libsecutils/src/storage/files_dv.c b/src/libsecutils/src/storage/files_dv.c
index 6025351e..81c7c690 100644
--- a/src/libsecutils/src/storage/files_dv.c
+++ b/src/libsecutils/src/storage/files_dv.c
@@ -63,7 +63,7 @@ static bool getBase64Password(OPTIONAL uta_ctx* ctx, const unsigned char* dv, ch
 #endif
     len = UTIL_base64_encode_to_buf(key, TA_OUTLEN, pw, MAX_B64_CHARS_PER_BYTE * TA_OUTLEN);
 
-    LOG(FL_TRACE, "DV-based password: %s", pw);
+    // better not do in productive builds: LOG(FL_TRACE, "DV-based password: %s", pw);
     return len >= 0;
 }
 
@@ -264,7 +264,7 @@ static char* get_basename(const char* path)
 /**
  * @brief returns canonicalized absolute path
  * @param path path which should be canonicalized
- * @param canonicalized
+ * @param pointer to buffer for canonicalized output, MUST be at least PATH_MAX characters long
  * @note  the pointer has to be freed by OPENSSL_free()
  */
 static char* get_canonicalized(const char* path, char* canonicalized)
@@ -276,7 +276,8 @@ static char* get_canonicalized(const char* path, char* canonicalized)
 
     if((0 not_eq dir_part) and (0 not_eq name_part))
     {
-        if(0 is_eq realpath(dir_part, canonicalized))
+        if(0 is_eq realpath(dir_part, canonicalized)
+           || strlen(canonicalized) + 1 + strlen(name_part) >= PATH_MAX)
         {
             ret_val = 0;
         }
diff --git a/src/libsecutils/src/storage/files_icv.c b/src/libsecutils/src/storage/files_icv.c
index 4d129b14..ba8b37b8 100644
--- a/src/libsecutils/src/storage/files_icv.c
+++ b/src/libsecutils/src/storage/files_icv.c
@@ -36,6 +36,7 @@
 /*
  * derive integrity protection hash for data with given len, using name as DV for key
  * optionally uses ctx pointer to UTA context, which typically is part of the libsecutils context
+ * if SECUTILS_USE_UTA is not set, cannot derive secure ICV
  * if returns true, hash value is placed in buf, which must be of size ICV_HEX_LEN+1
  */
 static bool calculate_icv_hex(OPTIONAL uta_ctx* ctx, const void* data, size_t len, const char* name, char* buf)
@@ -221,9 +222,7 @@ bool FILES_protect_icv_config_trusted(const char* file, OPTIONAL uta_ctx* ctx)
     int str_len = strlen(file);
     const char* name_tail = file + str_len - (str_len >= ext_len ? ext_len : 0);
     if(0 is_eq strcmp(name_tail, ".pem") or 0 is_eq strcmp(name_tail, ".crt")
-#ifdef SECUTILS_USE_ICV
        or 0 is_eq strcmp(name_tail, ".cnf") /* OpenSSL-style config file */
-#endif
     )
     {
         LOG(FL_INFO, "making sure that file '%s' has an ICV", file);
diff --git a/src/libsecutils/src/util/util.c b/src/libsecutils/src/util/util.c
index ca2447b5..5e2305aa 100644
--- a/src/libsecutils/src/util/util.c
+++ b/src/libsecutils/src/util/util.c
@@ -357,14 +357,15 @@ int UTIL_safe_string_copy(const char *source, OPTIONAL char *destination,
     }
 
     const char *begin = source;
-    size_t needed = 1;  /* record the buffer size that would be needed == strlen(source) */
-    while (*source != 0) {
+    size_t needed = 1;  /* record the buffer size that would be needed == strlen(source) + 1 */
+    while (*source != '\0') {
         needed++;
-        if (destination != NULL && needed < destination_len) {
-            *destination++ = *source++;
+        if (destination != NULL && needed <= destination_len) {
+            *destination++ = *source;
         }
+        source++;
     }
-     if (destination != NULL) {
+    if (destination != NULL) {
         *destination = '\0';
     }
 
@@ -372,7 +373,12 @@ int UTIL_safe_string_copy(const char *source, OPTIONAL char *destination,
         *size_needed = needed;
     }
 
-    return source - begin;
+    if (destination != NULL && needed > destination_len) {
+        /* source was truncated to fit destination buffer */
+        return -1;
+    }
+
+    return source - begin > INT_MAX ? -1 : (int)(source - begin);
 }
 
 /* implementation of the function url_encode */
@@ -427,7 +433,7 @@ size_t UTIL_url_encode(
     size_t needed = 0; /* record the size needed */
 
     for (is=0,id=0; source[is]!=0; ++is) {
-        if (unreserved[(int)source[is]]) {
+        if (unreserved[(unsigned char)source[is]]) {
             /* character is part of the unreserved ones */
             ++needed;
             if (destination && destination_len >= needed) {
diff --git a/src/util/icvutil.c b/src/util/icvutil.c
index 12b0900e..6981677a 100644
--- a/src/util/icvutil.c
+++ b/src/util/icvutil.c
@@ -5,7 +5,7 @@
 *
 * @copyright Copyright (c) Siemens Mobility GmbH, 2021
 *
-* @author David von Oheimb <david.von.oheimb@siemens.com>
+* @author Raphael Lisicki <raphael.lisicki@siemens.com>
 *
 * This work is licensed under the terms of the Apache Software License 
 * 2.0. See the COPYING file in the top-level directory.
@@ -33,7 +33,7 @@ int main(int argc, char *argv[]) {
         return ret;
     }
 #else
-    LOG(FL_WARN, "Not using UTA lib because SECUTILS_USE_UTA was not defined");
+    LOG(FL_WARN, "Not using UTA lib because SECUTILS_USE_UTA was not defined; cannot obtain secure ICV");
 #endif
 
     const char *prog = argv[0];