CVE-2026-42011
Publication date 7 May 2026
Last updated 22 May 2026
Ubuntu priority
Description
A flaw was found in gnutls. This vulnerability occurs because permitted name constraints were incorrectly ignored when previous Certificate Authorities (CAs) only had excluded name constraints. A remote attacker could exploit this to bypass critical name constraint checks during certificate validation. This bypass could lead to the acceptance of invalid certificates, potentially enabling spoofing or man-in-the-middle attacks against affected systems.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| gnutls28 | 26.04 LTS resolute |
Fixed 3.8.12-2ubuntu1.1
|
| 25.10 questing |
Fixed 3.8.9-3ubuntu2.2
|
|
| 24.04 LTS noble |
Fixed 3.8.3-1.1ubuntu3.6
|
|
| 22.04 LTS jammy |
Fixed 3.7.3-4ubuntu1.9
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Needs evaluation
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
7.4 · High
|
| Attack vector | Network |
| Attack complexity | High |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |
References
Related Ubuntu Security Notices (USN)
- USN-8284-1
- GnuTLS vulnerabilities
- 20 May 2026