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 products
gnu: gnutls; redhat: hardened images; redhat: openshift container platform; redhat: enterprise linux
References10
- access.redhat.com/security/cve/CVE-2026-42010 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2467289 Issue TrackingVendor Advisory
- access.redhat.com/security/cve/CVE-2026-42010 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2467289 Issue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:13274
- access.redhat.com/errata/RHSA-2026:20611
- access.redhat.com/errata/RHSA-2026:20612
- access.redhat.com/errata/RHSA-2026:20613
- access.redhat.com/errata/RHSA-2026:26319
- access.redhat.com/errata/RHSA-2026:26409
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 65 · as of 13 November 2026
- CWE
- CWE-170CWE-626
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.