diff --git a/.github/workflows/default.yml b/.github/workflows/default.yml
index bd47a5c4..98998b1b 100644
--- a/.github/workflows/default.yml
+++ b/.github/workflows/default.yml
@@ -18,10 +18,10 @@ jobs:
       - uses: actions/checkout@v4
 
       - name: Set up Java
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@v4
         with:
           distribution: 'adopt'
-          java-version: 17
+          java-version: 21
 
       - name: Gradle wrapper validation
         uses: gradle/wrapper-validation-action@859c33240bd026ce8d5f711f5adcc65c2f8eafc1 # https://github.com/gradle/wrapper-validation-action/issues/66
@@ -38,7 +38,7 @@ jobs:
 
       - name: Upload test results
         if: ${{ always() }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: test-results-${{ matrix.os }}
           path: "${{ github.workspace }}/**/build/reports/tests"
@@ -50,7 +50,7 @@ jobs:
       matrix:
         os: [ ubuntu-latest, windows-latest ]
         gradle: [ 8.4, current, release-candidate ]
-        java: [ 11, 17, 19 ]
+        java: [ 11, 17, 21 ]
 
     name: '[${{ matrix.os }}] Gradle: ${{ matrix.gradle }}, Java: ${{ matrix.java }}'
     steps:
@@ -59,7 +59,7 @@ jobs:
           fetch-depth: 0
 
       - name: Set up JDK
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@v4
         with:
           distribution: 'adopt'
           java-version: ${{ matrix.java }}
@@ -78,7 +78,7 @@ jobs:
 
       - name: Upload reports
         if: ${{ failure() }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: "test-project-reports-${{ matrix.os }}-${{ matrix.gradle }}-${{ matrix.java }}"
           path: "${{ github.workspace }}/**/build/reports/ktlint"
@@ -107,7 +107,7 @@ jobs:
       fail-fast: false
       matrix:
         gradle: [ current ]
-        java: [ 17 ]
+        java: [ 21 ]
         agp: ${{ fromJSON(needs.provide-agp-version-matrix.outputs.agp-versions) }}
 
     name: '[android] Gradle: ${{ matrix.gradle }}, Java: ${{ matrix.java }}, AGP: ${{ matrix.agp }}'
@@ -117,7 +117,7 @@ jobs:
           fetch-depth: 0
 
       - name: Set up JDK
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@v4
         with:
           distribution: 'adopt'
           java-version: ${{ matrix.java }}
@@ -137,7 +137,7 @@ jobs:
 
       - name: Upload reports
         if: ${{ failure() }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: "test-project-android-reports-${{ matrix.gradle }}-${{ matrix.java }}-${{ matrix.agp }}"
           path: "${{ github.workspace }}/**/build/reports/ktlint"
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 2ad981a6..bcb57fa5 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -13,10 +13,10 @@ jobs:
       - uses: actions/checkout@v4
 
       - name: Set up Java
-        uses: actions/setup-java@v3
+        uses: actions/setup-java@v4
         with:
           distribution: 'adopt'
-          java-version: 17
+          java-version: 21
 
       - name: Gradle wrapper validation
         uses: gradle/wrapper-validation-action@v1
diff --git a/README.md b/README.md
index 7ffb4c3e..13e55e79 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@ Available on the Gradle Plugins Portal: https://plugins.gradle.org/plugin/org.jm
 
 ```kotlin
 plugins {
-    id("org.jmailen.kotlinter") version "4.1.1"
+    id("org.jmailen.kotlinter") version "4.2.0"
 }
 ```
 
@@ -31,7 +31,7 @@ plugins {
 
 ```groovy
 plugins {
-    id "org.jmailen.kotlinter" version "4.1.1"
+    id "org.jmailen.kotlinter" version "4.2.0"
 }
 ```
 
@@ -45,7 +45,7 @@ Root `build.gradle.kts`
 
 ```kotlin
 plugins {
-    id("org.jmailen.kotlinter") version "4.1.1" apply false
+    id("org.jmailen.kotlinter") version "4.2.0" apply false
 }
 ```
 
@@ -65,7 +65,7 @@ Root `build.gradle`
 
 ```groovy
 plugins {
-    id 'org.jmailen.kotlinter' version "4.1.1" apply false
+    id 'org.jmailen.kotlinter' version "4.2.0" apply false
 }
 ```
 
@@ -83,6 +83,7 @@ plugins {
 
 | kotlinter version | min kotlin version | max kotlin version | min gradle version |
 |-------------------|--------------------|--------------------|--------------------|
+| 4.2.0+            | 1.9.20             | -                  | 8.4                |
 | 4.0.0+            | 1.9.0              | -                  | 7.6                |
 | 3.14.0+           | 1.8.0              | 1.8.22             | 7.6                |
 | 3.11.0+           | 1.7.0              | 1.7.22             | 7.0                |
diff --git a/build.gradle.kts b/build.gradle.kts
index 57ca9eea..0359889c 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -2,11 +2,11 @@ import org.jetbrains.kotlin.gradle.plugin.getKotlinPluginVersion
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 plugins {
-    kotlin("jvm") version "1.9.20"
+    kotlin("jvm") version "1.9.22"
     id("com.gradle.plugin-publish") version "1.1.0"
     `java-gradle-plugin`
     `maven-publish`
-    id("org.jmailen.kotlinter") version "4.1.0"
+    id("org.jmailen.kotlinter") version "4.1.1"
     idea
 }
 
@@ -20,15 +20,15 @@ val githubUrl = "https://github.com/jeremymailen/kotlinter-gradle"
 val webUrl = "https://github.com/jeremymailen/kotlinter-gradle"
 val projectDescription = "Lint and formatting for Kotlin using ktlint with configuration-free setup on JVM and Android projects"
 
-version = "4.1.1"
+version = "4.2.0"
 group = "org.jmailen.gradle"
 description = projectDescription
 
 object Versions {
-    const val androidTools = "7.3.1"
-    const val junit = "5.9.3"
-    const val ktlint = "1.0.1"
-    const val mockitoKotlin = "4.1.0"
+    const val ANDROID_TOOLS = "7.3.1"
+    const val JUNIT = "5.10.1"
+    const val KTLINT = "1.1.1"
+    const val MOCKITO_KOTLIN = "4.1.0"
 }
 
 configurations {
@@ -51,7 +51,7 @@ configurations {
 
 dependencies {
     compileOnly("org.jetbrains.kotlin:kotlin-gradle-plugin")
-    compileOnly("com.android.tools.build:gradle:${Versions.androidTools}")
+    compileOnly("com.android.tools.build:gradle:${Versions.ANDROID_TOOLS}")
 
     listOf(
         "ktlint-rule-engine",
@@ -62,20 +62,20 @@ dependencies {
         "ktlint-cli-reporter-html",
         "ktlint-cli-reporter-plain",
         "ktlint-cli-reporter-sarif",
-        "ktlint-ruleset-standard"
+        "ktlint-ruleset-standard",
     ).forEach { module ->
-        implementation("com.pinterest.ktlint:$module:${Versions.ktlint}")
+        implementation("com.pinterest.ktlint:$module:${Versions.KTLINT}")
     }
 
-    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:${Versions.junit}")
-    testImplementation("org.junit.jupiter:junit-jupiter-api:${Versions.junit}")
-    testImplementation("org.junit.jupiter:junit-jupiter-params:${Versions.junit}")
-    testImplementation("commons-io:commons-io:2.12.0")
-    testImplementation("org.mockito.kotlin:mockito-kotlin:${Versions.mockitoKotlin}")
+    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:${Versions.JUNIT}")
+    testImplementation("org.junit.jupiter:junit-jupiter-api:${Versions.JUNIT}")
+    testImplementation("org.junit.jupiter:junit-jupiter-params:${Versions.JUNIT}")
+    testImplementation("commons-io:commons-io:2.15.1")
+    testImplementation("org.mockito.kotlin:mockito-kotlin:${Versions.MOCKITO_KOTLIN}")
 }
 
 kotlin {
-    jvmToolchain(17)
+    jvmToolchain(21)
 }
 
 tasks {
@@ -115,7 +115,7 @@ tasks {
     }
 
     wrapper {
-        gradleVersion = "8.4"
+        gradleVersion = "8.5"
     }
 }
 
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
index 033e24c4..d64cd491 100644
Binary files a/gradle/wrapper/gradle-wrapper.jar and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 3fa8f862..1af9e093 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.5-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
diff --git a/gradlew b/gradlew
index fcb6fca1..1aa94a42 100755
--- a/gradlew
+++ b/gradlew
@@ -83,7 +83,8 @@ done
 # This is normally unused
 # shellcheck disable=SC2034
 APP_BASE_NAME=${0##*/}
-APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -144,7 +145,7 @@ if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
         # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045
+        # shellcheck disable=SC2039,SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
@@ -152,7 +153,7 @@ if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
       '' | soft) :;; #(
       *)
         # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC3045
+        # shellcheck disable=SC2039,SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -201,11 +202,11 @@ fi
 # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
 DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
-# Collect all arguments for the java command;
-#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
-#     shell script including quotes and variable substitutions, so put them in
-#     double quotes to make sure that they get re-expanded; and
-#   * put everything else in single quotes, so that it's not re-expanded.
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
diff --git a/test-project-android/build.gradle.kts b/test-project-android/build.gradle.kts
index 8888c969..64ca208e 100644
--- a/test-project-android/build.gradle.kts
+++ b/test-project-android/build.gradle.kts
@@ -1,5 +1,5 @@
 plugins {
-    kotlin("android") version "1.9.10"
+    kotlin("android") version "1.9.20"
     id("com.android.library")
     id("org.jmailen.kotlinter")
 }
diff --git a/test-project/build.gradle.kts b/test-project/build.gradle.kts
index 81370ba7..58e5b503 100644
--- a/test-project/build.gradle.kts
+++ b/test-project/build.gradle.kts
@@ -1,4 +1,4 @@
 plugins {
-    kotlin("jvm") version "1.9.10"
+    kotlin("jvm") version "1.9.20"
     id("org.jmailen.kotlinter")
 }