CVE-2026-44249
ADVISORY - githubSummary
Summary
An attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo(). Valid public IP addresses can bypass the restrictions.
Details
io.netty.handler.ipfilter.IpSubnetFilterRule#compareTo(java.net.InetSocketAddress) method performs a bitwise AND between the incoming IP address and the configured networkAddress, instead of the subnetMask.
Impact
Access Control Bypass. Attacker can bypass IpSubnetFilter IPv6 access controls.