CVE-2026-42012: gnutls. A remote attacker · CWE-295
Source GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in Red Hat Enterprise Linux 10 package updates : patch Red Hat Enterprise Linux 10 soon.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 28% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.3.29
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 26 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| gnutls | Affected
| Fixed in– |
AI-suggested
Red Hat has released security updates for GnuTLS in Red Hat Enterprise Linux 7 Extended Life Cycle Support that address this vulnerability (CVE-2026-42012) along with related issues. Users should apply the updated packages (e.g., gnutls-3.3.29-9.el7_9.2) as provided in Red Hat advisory RHSA-2026:43575. No additional mitigation actions are required beyond applying the official patches.
Description
A vulnerability in GnuTLS allows a remote attacker to bypass certificate validation by presenting a specially crafted certificate containing URI or SRV Subject Alternative Names (SANs). This causes the validation process to incorrectly fallback to checking DNS hostnames against the Common Name (CN), potentially enabling spoofing of legitimate services or interception of sensitive data. The issue affects specific versions of GnuTLS and has a CVSS score of 7.1, indicating high severity. Red Hat has released security updates addressing this and related vulnerabilities in GnuTLS for their Extended Life Cycle Support 7 product line.
References
- nvd.nist.gov/vuln/detail/CVE-2026-42012 (opens in a new tab)
- gnutls.org/security-new.html (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2467441 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-42012 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43575 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:41921 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:33125 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:32962 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30850 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30849 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30004 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:29197 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26409 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26319 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:20613 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:20612 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:20611 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:13274 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:58981 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:72502 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:74674 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:82888 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:82857 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:82372 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:82354 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:82347 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:82322 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:82304 (opens in a new tab)