High severity8.1NVD Advisory· Published Jun 8, 2026· Updated Jun 8, 2026
Netty has an IPv6 Subnet Filter Bypass via Incorrect Comparator Masking
CVE-2026-44249
Description
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.
Affected products
1Patches
0No patches discovered yet.
Vulnerability mechanics
No source-code context for this CVE — mechanics is only generated when we can read the actual fix diff. Without that, the four sections (root cause, attack vector, affected code, fix) would be speculation rather than analysis.
References
4News mentions
1- Netty: Four High-Severity DoS Vulnerabilities Disclosed TogetherVypr Intelligence · Jun 8, 2026