CVE-2026-56746 (GCVE-0-2026-56746)

Vulnerability from cvelistv5 – Published: 2026-07-21 21:36 – Updated: 2026-07-22 13:39
VLAI
Title
Netty has a Security Control Bypass via CORS Short-Circuit Failure
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 13:39 UTC
CWE
  • CWE-284 - Improper Access Control
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7868 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
netty netty Affected: >= 4.2.0.Final, < 4.2.16.Final
Affected: >= 4.1.0.Final, < 4.1.136.Final
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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