Vulnerability in GNU Gnutls
CVE-2026-42010
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.009 (60.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 60.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.009 · change: -0.001
Affected products
- GNU Gnutls
- Red Hat Ai Inference Server 3.2 — versions 1782951051, 1782951244, 1782951012
- Red Hat Discovery 2 — versions 1782159791, 1782166952
- Red Hat Enterprise Linux 10 — versions 0:3.8.10-4.el10_2
- Red Hat Enterprise Linux 10.0 Extended Update Support — versions 0:3.8.9-9.el10_0.19
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8 — versions 0:3.6.16-8.el8_10.6
- Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support — versions 0:3.6.14-10.el8_4.1, 0:4.13-3.el8_4.1
- Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On — versions 0:3.6.14-10.el8_4.1, 0:4.13-3.el8_4.1
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-42010 (vdb-entry, Vendor Advisory)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking, Issue Tracking, Vendor Advisory)
- access.redhat.com/errata/RHSA-2026:13274 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:20611 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:20613 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:20612 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:26319 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:26409 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:29197 (vendor-advisory)
- www.gnutls.org/security-new.html
Frequently asked questions
- What is CVE-2026-42010?
- CVE-2026-42010 is a high-severity vulnerability in GNU Gnutls, classified under Improper Null Termination. CVSS score: 7.1/10. Published 2026-05-07.
- How severe is CVE-2026-42010?
- High severity. CVSS v3 base score is 7.1 out of 10.