CVE-2026-88648
Published: October 9, 2026Last modified: October 20, 2026
Description
Incomplete X.509 implementation in GnuTLS v3.8.13 allows attackers controlling a subordinate Certificate Authority to bypass cross-domain PKI restrictions and issue unauthorized certificates.
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
- https://gist.github.com/lkloliver/1f2a97cb8d0b31aa27b6bd0354358d7d
- https://github.com/lkloliver/poc/tree/main/CVE-2026-88648
- https://gitlab.com/gnutls/gnutls/-/blob/e2169a87c7fb91935c2845088204b102baed4c5f/SECURITY.md
- https://gitlab.com/gnutls/gnutls/-/work_items/1965
- https://www.rfc-editor.org/rfc/rfc5280#section-4.2.1.10
- https://www.rfc-editor.org/rfc/rfc5280#section-6.1.4