עברית

Vulnerability Intelligence

CVE-2026-56820

Critical 9.1

Published
Last modified
NVD status
Analyzed

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.

Affected products

netty: netty

References5

Metrics

CVSS 3.1
9.1 CRITICAL Score source: NVD CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS — exploit probability
0% percentile: 25 · as of 14 November 2026
CWE
CWE-295

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