Vulnerability in Red Hat Discovery 2
CVE-2026-42013
A flaw was found in gnutls. When validating certificates, an oversized Subject Alternative Name (SAN) could cause the validation process to incorrectly fall back to checking the Common Name (CN) field. This could allow a remote attacker to bypass proper certificate validation, potentially leading to spoofing or man-in-the-middle attacks.
Vulnerability class: Improper Certificate Validation
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N.
EPSS exploit prediction
EPSS: 0.006 (45.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.001
Affected products
- 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 7 Extended Lifecycle Support — versions 0:3.3.29-9.el7_9.2
- 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
- Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support — versions 0:3.6.16-5.el8_6.5, 0:4.13-3.el8_6.2
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-42013 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
- 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
- access.redhat.com/errata/RHSA-2026:30004 (vendor-advisory)
Frequently asked questions
- What is CVE-2026-42013?
- CVE-2026-42013 is a high-severity vulnerability in Red Hat Discovery 2, classified under Improper Certificate Validation. CVSS score: 8.2/10. Published 2026-05-26.
- How severe is CVE-2026-42013?
- High severity. CVSS v3 base score is 8.2 out of 10.