diff --git a/build.gradle.kts b/build.gradle.kts
index 6215ec82b..a548c3ea2 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -9,7 +9,7 @@ plugins {
     id("com.jfrog.artifactory") version "5.2.5"
     id("org.sonarqube") version "7.2.3.7755"
     id("org.jetbrains.kotlin.jvm") apply false
-    id("com.diffplug.spotless") version "6.11.0"
+    id("com.diffplug.spotless") version "6.25.0"
     `maven-publish`
     signing
 }
diff --git a/gradle.properties b/gradle.properties
index b2044ab2d..f8f89cfab 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -2,5 +2,5 @@ group=org.sonarsource.kotlin
 version=3.6-SNAPSHOT
 description=Code Analyzer for Kotlin
 projectTitle=Kotlin
-kotlinVersion=2.3.20
+kotlinVersion=2.4.20-neptune-246
 org.gradle.jvmargs=-Xmx4096M
diff --git a/kotlin-checks-test-sources/build.gradle.kts b/kotlin-checks-test-sources/build.gradle.kts
index 2b26a9754..f7b762465 100644
--- a/kotlin-checks-test-sources/build.gradle.kts
+++ b/kotlin-checks-test-sources/build.gradle.kts
@@ -8,17 +8,17 @@ repositories {
 
 dependencies {
     implementation("org.jetbrains.kotlin:kotlin-stdlib")
-    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.5.1")
-    implementation("org.jetbrains.kotlin:kotlin-reflect:2.3.20")
-    implementation("org.jetbrains.kotlin:kotlin-test:2.3.20")
-    implementation("org.jetbrains.kotlin:kotlin-test-junit5:2.3.20")
-    implementation("com.squareup.okhttp3:okhttp:4.9.0")
-    implementation("commons-net:commons-net:3.8.0")
-    implementation("org.springframework.security:spring-security-crypto:5.7.2")
-    implementation("org.springframework.security:spring-security-core:4.2.17.RELEASE")
-    implementation("commons-codec:commons-codec:1.13")
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.10.2")
+    implementation("org.jetbrains.kotlin:kotlin-reflect:2.4.20-neptune-246")
+    implementation("org.jetbrains.kotlin:kotlin-test:2.4.20-neptune-246")
+    implementation("org.jetbrains.kotlin:kotlin-test-junit5:2.4.20-neptune-246")
+    implementation("com.squareup.okhttp3:okhttp:4.12.0")
+    implementation("commons-net:commons-net:3.13.0")
+    implementation("org.springframework.security:spring-security-crypto:5.8.16")
+    implementation("org.springframework.security:spring-security-core:4.2.20.RELEASE")
+    implementation("commons-codec:commons-codec:1.21.0")
     implementation("com.google.guava:guava:30.1.1-jre")
-    implementation("org.apache.commons:commons-lang3:3.17.0")
+    implementation("org.apache.commons:commons-lang3:3.20.0")
     implementation("commons-lang:commons-lang:2.6")
 }
 
diff --git a/sonar-kotlin-api/build.gradle.kts b/sonar-kotlin-api/build.gradle.kts
index b83f7664f..a1547040a 100644
--- a/sonar-kotlin-api/build.gradle.kts
+++ b/sonar-kotlin-api/build.gradle.kts
@@ -22,7 +22,7 @@ dependencies {
             isTransitive = false
         }
     }
-    implementation("org.jetbrains.kotlinx:kotlinx-serialization-core:1.10.0")
+    implementation("org.jetbrains.kotlinx:kotlinx-serialization-core:1.11.0")
     implementation("com.github.ben-manes.caffeine:caffeine:2.9.3")
     compileOnly(libs.sonar.plugin.api)
     compileOnly(libs.slf4j.api)
diff --git a/sonar-kotlin-plugin/build.gradle.kts b/sonar-kotlin-plugin/build.gradle.kts
index 91f56ed62..76988b43f 100644
--- a/sonar-kotlin-plugin/build.gradle.kts
+++ b/sonar-kotlin-plugin/build.gradle.kts
@@ -20,7 +20,7 @@ ruleApi {
 
 buildscript {
     dependencies {
-        classpath("com.guardsquare:proguard-gradle:7.6.1")
+        classpath("com.guardsquare:proguard-gradle:7.9.1")
     }
 }