CVE-2026-56746

medium

Published 2026-07-21 · Modified 2026-07-22

💬 Discuss on Community ✚ Propose mitigation

CVSS v3

6.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

CVSS v4 NEW

—

not yet in upstream

VIR risk

6.5

Description

Netty is a network application framework for development of protocol servers and clients. Versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, are vulnerable to security control bypass during the origin evaluation process. CorsHandler provides a shortCircuit() configuration designed to reject unauthorized cross-origin requests immediately, acting as a security control before requests reach the application. However, due to a logical operator error in the origin evaluation process, this protection can be entirely bypassed. An attacker can bypass the short-circuit mechanism by sending a request with an Origin: null header. This failure forwards unauthorized requests to the backend application, bypassing intended access controls. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

Predictions

Exploit likelihood

75%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

SUSE Affected 1 release

Version	Status	Fixed in
—	Affected	—

References

CWEs

CWE-284

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.