CVE-2026-56821

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Source
https://cve.org/CVERecord?id=CVE-2026-56821
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-56821.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-56821
Aliases
Downstream
Related
Published
2026-07-28T23:07:13.616Z
Modified
2026-08-12T03:30:18.549974301Z
Severity
  • 7.4 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N CVSS Calculator
Summary
Netty: Out-of-date OCSP Responses Accepted by OcspServerCertificateValidator
Details

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 Prior to versions 4.1.136.Final and 4.2.16.Final, the OcspServerCertificateValidator flags an out-of-date OCSP response but does not stop processing it, so an expired GOOD response is still reported as VALID, letting an on-path attacker replay a stale GOOD response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.

Database specific 
{
    "cwe_ids": [
        "CWE-299"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56821.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/netty/netty

Affected ranges

Type
GIT
Repo
https://github.com/netty/netty
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
fca0764703b3bb59c6e6dc5d29c6d9710d35c0e6
Introduced
09e64d259c99be8b5b2a471a78f11e65eb82598a
Fixed
3703d79669ee024f6483c9d8697ac58ba546df33
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "4.1.136"
        },
        {
            "introduced": "4.2.0"
        },
        {
            "fixed": "4.2.16"
        }
    ],
    "source": "CPE_RANGE",
    "cpe": "cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*"
}

Affected versions

netty-4.*
netty-4.0.0.Alpha1
netty-4.0.0.Alpha2
netty-4.0.0.Alpha3
netty-4.0.0.Alpha4
netty-4.0.0.Alpha5
netty-4.0.0.Alpha6
netty-4.0.0.Alpha7
netty-4.0.0.Alpha8
netty-4.0.0.Beta1
netty-4.0.0.Beta2
netty-4.0.0.Beta3
netty-4.0.0.CR1
netty-4.0.0.CR2
netty-4.0.0.CR3
netty-4.0.0.CR4
netty-4.0.0.CR5
netty-4.0.0.CR7
netty-4.0.0.CR8
netty-4.0.0.CR9
netty-4.0.0.Final
netty-4.0.1.Final
netty-4.0.10.Final
netty-4.0.11.Final
netty-4.0.12.Final
netty-4.0.13.Final
netty-4.0.14.Beta1
netty-4.0.14.Final
netty-4.0.15.Final
netty-4.0.2.Final
netty-4.0.3.Final
netty-4.0.4.Final
netty-4.0.5.Final
netty-4.0.6.Final
netty-4.0.7.Final
netty-4.0.8.Final
netty-4.1.0.Beta1
netty-4.1.0.Beta2
netty-4.1.0.Beta3
netty-4.1.0.Beta4
netty-4.1.0.Beta5
netty-4.1.0.Beta6
netty-4.1.0.Beta7
netty-4.1.0.Beta8
netty-4.1.0.CR1
netty-4.1.0.CR2
netty-4.1.0.CR3
netty-4.1.0.CR4
netty-4.1.0.CR5
netty-4.1.0.CR6
netty-4.1.0.CR7
netty-4.1.0.Final
netty-4.1.1.Final
netty-4.1.10.Final
netty-4.1.100.Final
netty-4.1.101.Final
netty-4.1.102.Final
netty-4.1.103.Final
netty-4.1.104.Final
netty-4.1.105.Final
netty-4.1.106.Final
netty-4.1.107.Final
netty-4.1.108.Final
netty-4.1.109.Final
netty-4.1.11.Final
netty-4.1.110.Final
netty-4.1.111.Final
netty-4.1.112.Final
netty-4.1.113.Final
netty-4.1.114.Final
netty-4.1.115.Final
netty-4.1.116.Final
netty-4.1.117.Final
netty-4.1.118.Final
netty-4.1.119.Final
netty-4.1.12.Final
netty-4.1.120.Final
netty-4.1.121.Final
netty-4.1.122.Final
netty-4.1.123.Final
netty-4.1.124.Final
netty-4.1.125.Final
netty-4.1.126.Final
netty-4.1.127.Final
netty-4.1.128.Final
netty-4.1.129.Final
netty-4.1.13.Final
netty-4.1.130.Final
netty-4.1.131.Final
netty-4.1.132.Final
netty-4.1.133.Final
netty-4.1.134.Final
netty-4.1.135.Final
netty-4.1.14.Final
netty-4.1.15.Final
netty-4.1.16.Final
netty-4.1.17.Final
netty-4.1.18.Final
netty-4.1.19.Final
netty-4.1.2.Final
netty-4.1.20.Final
netty-4.1.21.Final
netty-4.1.22.Final
netty-4.1.23.Final
netty-4.1.24.Final
netty-4.1.25.Final
netty-4.1.26.Final
netty-4.1.27.Final
netty-4.1.28.Final
netty-4.1.29.Final
netty-4.1.3.Final
netty-4.1.30.Final
netty-4.1.31.Final
netty-4.1.32.Final
netty-4.1.33.Final
netty-4.1.34.Final
netty-4.1.35.Final
netty-4.1.36.Final
netty-4.1.37.Final
netty-4.1.38.Final
netty-4.1.39.Final
netty-4.1.4.Final
netty-4.1.40.Final
netty-4.1.41.Final
netty-4.1.42.Final
netty-4.1.43.Final
netty-4.1.44.Final
netty-4.1.45.Final
netty-4.1.46.Final
netty-4.1.47.Final
netty-4.1.48.Final
netty-4.1.49.Final
netty-4.1.5.Final
netty-4.1.50.Final
netty-4.1.51.Final
netty-4.1.52.Final
netty-4.1.53.Final
netty-4.1.54.Final
netty-4.1.55.Final
netty-4.1.56.Final
netty-4.1.57.Final
netty-4.1.58.Final
netty-4.1.59.Final
netty-4.1.6.Final
netty-4.1.60.Final
netty-4.1.61.Final
netty-4.1.62.Final
netty-4.1.63.Final
netty-4.1.64.Final
netty-4.1.65.Final
netty-4.1.66.Final
netty-4.1.67.Final
netty-4.1.68.Final
netty-4.1.69.Final
netty-4.1.7.Final
netty-4.1.70.Final
netty-4.1.71.Final
netty-4.1.72.Final
netty-4.1.73.Final
netty-4.1.74.Final
netty-4.1.75.Final
netty-4.1.76.Final
netty-4.1.77.Final
netty-4.1.78.Final
netty-4.1.79.Final
netty-4.1.8.Final
netty-4.1.80.Final
netty-4.1.81.Final
netty-4.1.82.Final
netty-4.1.83.Final
netty-4.1.84.Final
netty-4.1.85.Final
netty-4.1.86.Final
netty-4.1.87.Final
netty-4.1.88.Final
netty-4.1.89.Final
netty-4.1.9.Final
netty-4.1.90.Final
netty-4.1.91.Final
netty-4.1.92.Final
netty-4.1.93.Final
netty-4.1.94.Final
netty-4.1.95.Final
netty-4.1.96.Final
netty-4.1.97.Final
netty-4.1.98.Final
netty-4.1.99.Final
netty-4.2.0.Final
netty-4.2.1.Final
netty-4.2.10.Final
netty-4.2.11.Final
netty-4.2.12.Final
netty-4.2.13.Final
netty-4.2.14.Final
netty-4.2.15.Final
netty-4.2.2.Final
netty-4.2.3.Final
netty-4.2.4.Final
netty-4.2.5.Final
netty-4.2.6.Final
netty-4.2.7.Final
netty-4.2.8.Final
netty-4.2.9.Final

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-56821.json"