CVE-2026-56820 (GCVE-0-2026-56820)
Vulnerability from cvelistv5
Published
2026-07-21 22:26
Modified
2026-07-24 20:12
Severity ?
7.4 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE
  • CWE-295 - Improper Certificate Validation
Summary
Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and prior to 4.1.135.Final, `OcspClient` does not validate that the `CertificateID` in an OCSP response matches the requested `CertificateID`, which can lead to replay attack. `OcspClient.validateResponse` accepts a legitimately signed `GOOD` status response for an unrelated certificate issued by the same CA, allowing bypass of revocation checks for another certificate. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.
References
Impacted products
Vendor Product Version
netty netty Version: >= 4.2.0.Final, < 4.2.16.Final
Version: < 4.1.136.Final
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