diff --git a/CHANGES.txt b/CHANGES.txt
index 4c46695a89..3307fb3d9c 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,5 +1,4 @@
 3.9
- * Partial revert of CASSANDRA-11971, cannot recycle buffer in SP.sendMessagesToNonlocalDC (CASSANDRA-11950)
  * Fix hdr logging for single operation workloads (CASSANDRA-12145)
  * Fix SASI PREFIX search in CONTAINS mode with partial terms (CASSANDRA-12073)
  * Increase size of flushExecutor thread pool (CASSANDRA-12071)
@@ -29,6 +28,8 @@ Merged from 2.1:
 
 
 3.8
+ * Partial revert of CASSANDRA-11971, cannot recycle buffer in SP.sendMessagesToNonlocalDC (CASSANDRA-11950)
+ * Upgrade netty to 4.0.39 (CASSANDRA-12032, CASSANDRA-12034)
  * Improve details in compaction log message (CASSANDRA-12080)
  * Allow unset values in CQLSSTableWriter (CASSANDRA-11911)
  * Chunk cache to request compressor-compatible buffers if pool space is exhausted (CASSANDRA-11993)
diff --git a/build.xml b/build.xml
index d151431048..e13fdc0857 100644
--- a/build.xml
+++ b/build.xml
@@ -426,7 +426,7 @@
           <dependency groupId="com.addthis.metrics" artifactId="reporter-config3" version="3.0.0" />
           <dependency groupId="org.mindrot" artifactId="jbcrypt" version="0.3m" />
           <dependency groupId="io.airlift" artifactId="airline" version="0.6" />
-          <dependency groupId="io.netty" artifactId="netty-all" version="4.0.36.Final" />
+          <dependency groupId="io.netty" artifactId="netty-all" version="4.0.39.Final" />
           <dependency groupId="com.google.code.findbugs" artifactId="jsr305" version="2.0.2" />
           <dependency groupId="com.clearspring.analytics" artifactId="stream" version="2.5.2" />
           <dependency groupId="com.datastax.cassandra" artifactId="cassandra-driver-core" version="3.0.1" classifier="shaded">
diff --git a/lib/licenses/netty-all-4.0.36.Final.txt b/lib/licenses/netty-all-4.0.39.Final.txt
similarity index 100%
rename from lib/licenses/netty-all-4.0.36.Final.txt
rename to lib/licenses/netty-all-4.0.39.Final.txt
diff --git a/lib/netty-all-4.0.36.Final.jar b/lib/netty-all-4.0.36.Final.jar
deleted file mode 100644
index 5e278c4dbe..0000000000
Binary files a/lib/netty-all-4.0.36.Final.jar and /dev/null differ
diff --git a/lib/netty-all-4.0.39.Final.jar b/lib/netty-all-4.0.39.Final.jar
new file mode 100644
index 0000000000..3f5b3e68a6
Binary files /dev/null and b/lib/netty-all-4.0.39.Final.jar differ