From ee2c3ba85bb17c3b1bb5600b3e6f44584183a6a0 Mon Sep 17 00:00:00 2001
From: Jeff Thomas <jeffrey.thomas@t-systems.com>
Date: Wed, 12 Feb 2025 00:16:27 +0100
Subject: [PATCH 1/2] Fixed handling of null 'replacement' parameter in
 RegexReplacement#createRegexReplacement (#3215)

* per other builder methods in Log4j a invalid input parameter should result in a fas-fail returning null
---
 .../logging/log4j/core/pattern/RegexReplacement.java   |  3 ++-
 src/changelog/2.25.0/3215_fix-RegexReplacement.xml     | 10 ++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)
 create mode 100644 src/changelog/2.25.0/3215_fix-RegexReplacement.xml

diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/RegexReplacement.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/RegexReplacement.java
index 448c43858bd..8446afd53b8 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/RegexReplacement.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/RegexReplacement.java
@@ -65,7 +65,7 @@ public String toString() {
      * Create a RegexReplacement.
      * @param regex The regular expression to locate.
      * @param replacement The replacement value.
-     * @return A RegexReplacement.
+     * @return the new RegexReplacement instance or {@code null} if an input parameter was invalid
      */
     @PluginFactory
     public static RegexReplacement createRegexReplacement(
@@ -76,6 +76,7 @@ public static RegexReplacement createRegexReplacement(
         }
         if (replacement == null) {
             LOGGER.error("A replacement string is required to perform replacement");
+            return null;
         }
         // FIXME: should we use Matcher.quoteReplacement() here?
         return new RegexReplacement(regex, replacement);
diff --git a/src/changelog/2.25.0/3215_fix-RegexReplacement.xml b/src/changelog/2.25.0/3215_fix-RegexReplacement.xml
new file mode 100644
index 00000000000..08890d7ecf1
--- /dev/null
+++ b/src/changelog/2.25.0/3215_fix-RegexReplacement.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<entry xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xmlns="https://logging.apache.org/xml/ns"
+       xsi:schemaLocation="https://logging.apache.org/xml/ns https://logging.apache.org/xml/ns/log4j-changelog-0.xsd"
+       type="fixed">
+  <issue id="3215" link="https://github.com/apache/logging-log4j2/issues/3215"/>
+  <description format="asciidoc">
+    Properly handle null 'replacement' parameter in RegexReplacement#createRegexReplacement.
+  </description>
+</entry>

From 59bc4b5905604917464ad0f028b81fea7bae1886 Mon Sep 17 00:00:00 2001
From: Jeff Thomas <jeffrey.thomas@t-systems.com>
Date: Sun, 16 Feb 2025 20:45:05 +0100
Subject: [PATCH 2/2] Moved changelog to .2.x.x per PR Code Review (#3215)

---
 src/changelog/{2.25.0 => .2.x.x}/3215_fix-RegexReplacement.xml | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename src/changelog/{2.25.0 => .2.x.x}/3215_fix-RegexReplacement.xml (100%)

diff --git a/src/changelog/2.25.0/3215_fix-RegexReplacement.xml b/src/changelog/.2.x.x/3215_fix-RegexReplacement.xml
similarity index 100%
rename from src/changelog/2.25.0/3215_fix-RegexReplacement.xml
rename to src/changelog/.2.x.x/3215_fix-RegexReplacement.xml