Description
Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, the OcspServerCertificateValidator flags an out-of-date OCSP response but does not stop processing it, so an expired GOOD response is still reported as VALID, letting an on-path attacker replay a stale GOOD response to bypass revocation of a since-revoked certificate. Exploitation can lead to certificate revocation bypass via replay of an expired OCSP response. Any application using OcspServerCertificateValidator is affected; a revoked certificate can be accepted. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.
Affected products
netty: netty
References2
- github.com/netty/netty/security/advisories/GHSA-g7hg-vrcf-mvmr ExploitVendor Advisory
- github.com/netty/netty/security/advisories/GHSA-g7hg-vrcf-mvmr ExploitVendor Advisory
Metrics
- CVSS 3.1
-
7.4
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 13 · as of 13 November 2026
- CWE
- CWE-299
Could this be exploited in your environment?
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