CVE-2026-56746

Netty has a Security Control Bypass via CORS Short-Circuit Failure

MEDIUM 6.5

At a glance

Source
NVD
EPSS
EPSS 0.41 % · percentile 35 ()
State
PUBLISHED
Published
Updated
Assigner
GitHub_M
NVD status
Analyzed

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.

Weaknesses (CWE)

  • CWE-284 — Improper Access Control

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:NGitHub_M
CVSS 3.1MEDIUM 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:NNVD · security-advisories@github.com (Secondary)

Advisories

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
netty · nettyaffected >= 4.2.0.Final, < 4.2.16.Final ; affected >= 4.1.0.Final, < 4.1.136.Final

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD