CVE-2026-42010
Medium
Elevated severity or exploit probability.
CVSS base
7.1
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
EPSS — probability of exploitation (30 days)
1.1%
62.7th percentile
CISA KEV
Not listed
Weakness / dates
CWE-170
Published 2026-05-07 · modified 2026-09-18
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | L | Low |
| Availability | N | None |
Timeline
- 2026-05-07 — Published (NVD)
- 2026-09-18 — Last modified (NVD)
Description
A flaw was found in gnutls. Servers configured with RSA-PSK (Rivest–Shamir–Adleman – Pre-Shared Key) wrongfully matched usernames containing a NUL character with truncated usernames. A remote attacker could exploit this by sending a specially crafted username, leading to an authentication bypass. This vulnerability allows an attacker to gain unauthorized access by circumventing the authentication process.
Affected
References
- https://access.redhat.com/errata/RHSA-2026:13274
- https://access.redhat.com/errata/RHSA-2026:20611
- https://access.redhat.com/errata/RHSA-2026:20612
- https://access.redhat.com/errata/RHSA-2026:20613
- https://access.redhat.com/errata/RHSA-2026:26319
- https://access.redhat.com/errata/RHSA-2026:26409
- https://access.redhat.com/errata/RHSA-2026:29197
- https://access.redhat.com/errata/RHSA-2026:30004
- https://access.redhat.com/errata/RHSA-2026:30849
- https://access.redhat.com/errata/RHSA-2026:30850
- https://access.redhat.com/errata/RHSA-2026:32962
- https://access.redhat.com/errata/RHSA-2026:33125
- https://access.redhat.com/errata/RHSA-2026:34764
- https://access.redhat.com/errata/RHSA-2026:34788
- https://access.redhat.com/errata/RHSA-2026:34790
- https://access.redhat.com/errata/RHSA-2026:36004
- https://access.redhat.com/errata/RHSA-2026:36005
- https://access.redhat.com/errata/RHSA-2026:36006
- https://access.redhat.com/errata/RHSA-2026:40762
- https://access.redhat.com/errata/RHSA-2026:41921
- https://access.redhat.com/errata/RHSA-2026:56853
- https://access.redhat.com/errata/RHSA-2026:57483
- https://access.redhat.com/errata/RHSA-2026:58981
- https://access.redhat.com/errata/RHSA-2026:59831
- https://access.redhat.com/errata/RHSA-2026:60019
- https://access.redhat.com/errata/RHSA-2026:62409
- https://access.redhat.com/errata/RHSA-2026:65839
- https://access.redhat.com/security/cve/CVE-2026-42010
- https://bugzilla.redhat.com/show_bug.cgi?id=2467289
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-4