CVE-2026-67693

Status: Awaiting AnalysisHigh (7.5)—

An issue in gnutls v.3.8.13 allows an attacker to obtain sensitive information via failing to reject end-entity X.509 certificates that contain a contradictory combination of Key Usage (KU) and Extended Key Usage (EKU)

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Base score: 7.5

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.19%
Percentile among all scored CVEs: 8
Score date: 10/16/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access85 %
Primary impactT1552.004 Private Keyscredential access75 %

Vulnerabilidad de red sin autenticación (AV:N/PR:N) que permite obtener información sensible mediante certificados X.509 malformados; información de criptografía/PKI es credencial.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Vulnerability Scanning Restrict File and Directory Permissions Privileged Account Management Password Policies Network Segmentation Limit Access to Resource Over Network

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

GNU — Gnutls^AI

CWEs

CWE-367

References

Raw JSON (NVD)

Show

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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
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          "attackComplexity": "LOW",
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  "published": "2026-10-08T19:18:41.280",
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      "url": "http://gnutls.com",
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  "lastModified": "2026-10-16T18:18:00.667",
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