VULNERABILITY INTELLIGENCE
CVE-2026-56820
CVSS score7.4 HIGH
EPSS probability0.31%
CISA KEVNot currently listed
Published2026-07-21
Last modified2026-07-30
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Description
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.
Weakness classification
- security-advisories@github.com: CWE-295
Primary references
- security-advisories@github.com — Patch
- security-advisories@github.com — Patch
- security-advisories@github.com — Release Notes
- security-advisories@github.com — Release Notes
- security-advisories@github.com — Exploit, Vendor Advisory