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CVE-2026-56820

Netty: Missing CertificateID Validation in OCSP Response Allows Replay Attacks

Published: Jul 21, 2026Updated: Jul 30, 2026 Sources: CVE List NVDCWE-295
7.4HIGH
NVD MITRE
EPSS Score
0.2%
Top 92.1%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-295

Affected Products

netty
oss-projectaka netty-incubator-codec-ohttp, io.netty:netty
nettyLibraryLibrary
OSS Libraries / generic-library

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Collection
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References

https://github.com/netty/netty/security/advisories/GHSA-272m-gcwp-mpwg
github.com
https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b
github.com
https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6
github.com
and 2 more references View all →

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