CVE-2026-56820Netty is a network application framework for development of protocol servers and clients.
Updated under an hour ago ()
Does this affect you?
It affects netty. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
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.
- CVSS
- 9.1 CRITICAL (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Weakness (CWE)
- CWE-295
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Not given
- NVD analysis
- Analyzed
- Record last updated
- Jul 30, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
netty netty netty:netty | before 4.1.136; from 4.2.0 before 4.2.16 | NVD |
References
- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003bpatch
- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6patch
- https://github.com/netty/netty/releases/tag/netty-4.1.136.Finalrelease-notes
- https://github.com/netty/netty/releases/tag/netty-4.2.16.Finalrelease-notes
- https://github.com/netty/netty/security/advisories/GHSA-272m-gcwp-mpwgexploit, vendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.