A AegiFlow
HIGHCVSS 7.4EPSS 0.3%

CVE-2026-56820

CVE-2026-56820 updated by NVD

Published
2026-07-22
Modified
2026-07-31
EPSS percentile
22%
Sources
github-advisory, nvd

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.

Affected packages

EcosystemPackageAffected versionsFixed versions
Mavenio.netty:netty-handler-ssl-ocsp4.2.16.Final, 4.1.136.Final

Remediation: Upgrade to 4.2.16.Final or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

CVE® is a registered trademark of The MITRE Corporation. CVE content reproduced under the CVE Terms of Use; copyright designation © MITRE.

EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.