CVE-2026-67693
Published: October 9, 2026Last modified: October 20, 2026
Description
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)
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 3.7 |
| Attack Vector | NETWORK |
| Attack complexity | HIGH |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | LOW |
| Integrity impact | NONE |
| Availability impact | NONE |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | gnutls | Not affected (3.7.8-r2) |
| 25 LTS | gnutls | Not affected (3.8.8-r0) | |
| Stream | gnutls | Not affected (3.8.0-r3) |
References
- http://gnutls.com
- https://gist.github.com/lkloliver/6fbfc191bc6163942c8017551ac3f238
- https://github.com/lkloliver/poc/tree/main/CVE-2026-67693
- https://gitlab.com/gnutls/gnutls/-/blob/3.8.13/lib/x509/verify.c#L1119-1178
- https://gitlab.com/gnutls/gnutls/-/blob/e2169a87c7fb91935c2845088204b102baed4c5f/SECURITY.md
- https://gitlab.com/gnutls/gnutls/-/work_items/1642
- https://gitlab.com/gnutls/gnutls/-/work_items/1965