Fix Python 3.13 telnetlib import

core/checks.py

@@ -22,7 +22,6 @@
 from core.clis import Shell, MultilineShell
 from core.tcpserver import TcpServer
 import time
-import telnetlib
 import sys
 
 if sys.version_info.major > 2 :
@@ -54,6 +53,16 @@
     Ejs
 ]
 
+def _interact_with_telnet(hostname, port, timeout = 5):
+    try:
+        from telnetlib import Telnet
+    except ImportError:
+        log.error("The --bind-shell option requires telnetlib. On Python 3.13 or newer, install standard-telnetlib.")
+        return False
+
+    Telnet(hostname, port, timeout = timeout).interact()
+    return True
+
 def _print_injection_summary(channel):
 
     prefix = channel.data.get('prefix', '').replace('\n', '\\n')
@@ -285,11 +294,11 @@ def check_template_injection(channel):
 
                 try:
 
-                    telnetlib.Telnet(urlparsed.hostname, bind_shell_port, timeout = 5).interact()
+                    if _interact_with_telnet(urlparsed.hostname, bind_shell_port):
 
-                    # If telnetlib does not rise an exception, we can assume that
-                    # ended correctly and return from `run()`
-                    return
+                        # If telnetlib does not rise an exception, we can assume that
+                        # ended correctly and return from `run()`
+                        return
                 except Exception as e:
                     log.debug(
                         "Error connecting to %s:%i %s" % (

requirements.txt

@@ -3,5 +3,6 @@ certifi==2018.10.15
 chardet==3.0.4
 idna==2.8
 requests==2.22.0
+standard-telnetlib==3.13.0; python_version >= "3.13"
 urllib3==1.24.1
 wsgiref==0.1.2