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.
CVE-2026-42010
CVSS base score
7.1 (v3.1)
Severity
HIGH
Attack vector
Network
Weakness
CWE-170, CWE-626
Last modified
October 30, 2026
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
Affected products
gnu gnutls
redhat hardened images
redhat openshift container platform
redhat enterprise linux