diff --git a/CHANGES.md b/CHANGES.md
index 9d19dfb644..0244972a68 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,19 @@
+# Synapse 1.164.1 (2026-10-28)
+
+## Bugfixes
+
+- Fix clearing user status for clients that send a `null` profile field value.
+
+  When `include_profile_updates_in_sync` is enabled, Synapse will continue to accept `null` custom profile field values
+  until clients have had a sufficient time to change their behaviour. This special casing is tracked in [this issue](https://github.com/element-hq/synapse/issues/20424). ([\#20422](https://github.com/element-hq/synapse/issues/20422))
+
+## Internal Changes
+
+- Bump `msgpack` from `1.2.1` to `1.2.4` to address [`GHSA-j586-36cw-2gc2`](https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2) which can cause memory exhaustion problems when malformed tokens are used with the public room list API's. ([\#20421](https://github.com/element-hq/synapse/issues/20421))
+
+
+
+
 # Synapse 1.164.0 (2026-10-27)
 
 No significant changes since 1.164.0rc3.
diff --git a/debian/changelog b/debian/changelog
index bffab31a4b..8be78124a8 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.164.1) stable; urgency=medium
+
+  * New synapse release 1.164.1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Wed, 28 Oct 2026 18:05:53 +0000
+
 matrix-synapse-py3 (1.164.0) stable; urgency=medium
 
   * New synapse release 1.164.0.
diff --git a/pyproject.toml b/pyproject.toml
index 7b7ebe8400..02db363597 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "matrix-synapse"
-version = "1.164.0"
+version = "1.164.1"
 description = "Homeserver for the Matrix decentralised comms protocol"
 readme = "README.rst"
 authors = [