CVE-2026-95210

gnutls: gnutls: certificates with invalid extensions incorrectly accepted

Published Oct 8, 2026 CVSS 3.1 · 4.8 Medium EPSS < 1% KEV · Not listed
Description
GnuTLS v3.8.13 does not reject a critical keyUsage extension when it cannot be processed, such as when extnValue is an ASN.1 NULL (05 00) instead of a BIT STRING. NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Description Improper certificate validation in gnutls v3.8.13 causes the application to accept certificates containing invalid extensions. GnuTLS v3.8.13 does not reject a critical keyUsage extension when it cannot be processed, such as when extnValue is an ASN.1 NULL (05 00) instead of a BIT STRING. NOTE: the Supplier does not consider this an actionable security vulnerability because of its "threat model doesn't consider attacks only possible by modifying anything within the trust boundary (private keys, trusted certificate authorities and their issued certificates including intermediate CAs, etc.)" policy.
References
Type Values Removed Values Added
Title Certificate Validation Bypass due to Invalid Extensions gnutls: gnutls: certificates with invalid extensions incorrectly accepted
References
Metrics threat_severity

None

threat_severity

Moderate

Type Values Removed Values Added
Title Certificate Validation Bypass due to Invalid Extensions
Type Values Removed Values Added
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

cvssV3_1

{'score': 4.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Gnu
Gnu gnutls
Vendors & Products Gnu
Gnu gnutls
Type Values Removed Values Added
Title GnuTLS 3.8.13 improper certificate validation permits acceptance of certificates with invalid extensions
Type Values Removed Values Added
Title GnuTLS 3.8.13 improper certificate validation permits acceptance of certificates with invalid extensions
Type Values Removed Values Added
Weaknesses CWE-295
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

Type Values Removed Values Added
Description Improper certificate validation in gnutls v3.8.13 causes the application to accept certificates containing invalid extensions.
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Nov 4, 2026, 4:54 AM
Reserved
Sep 22, 2026, 12:00 AM
Status
Awaiting Analysis
Published
Oct 8, 2026, 6:18 PM
Modified
Nov 4, 2026, 5:19 AM
Severity
Moderate
Public date
Oct 8, 2026, 12:00 AM