diff --git a/Release.md b/Release.md
index 4716e374..33fc0aea 100644
--- a/Release.md
+++ b/Release.md
@@ -6,3 +6,4 @@
 
 * Fixed a server panic and remote denial of service caused by a client sending a negative `pool_count`. Negative values are now rejected before work-connection pool resources are allocated.
 * Fixed `frpc verify` ignoring configured `featureGates`, which caused VirtualNet configurations to be rejected even when the feature was enabled.
+* Fixed a case-insensitive validation bypass that allowed `customDomains` under the configured `subDomainHost` to be registered using mixed-case domain names.