CVE-2026-42012 (GCVE-0-2026-42012)
Vulnerability from cvelistv5
Published
2026-05-26 21:29
Modified
2026-06-02 15:34
CWE
  • CWE-295 - Improper Certificate Validation
Summary
A flaw was found in gnutls. A remote attacker could exploit this vulnerability by presenting a specially crafted certificate that contains Uniform Resource Identifier (URI) or Service (SRV) Subject Alternative Names (SANs). This could cause the certificate validation process to incorrectly fall back to checking DNS hostnames against the Common Name (CN), potentially allowing the attacker to spoof legitimate services or intercept sensitive information.
References
https://access.redhat.com/errata/RHSA-2026:20611 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:20612 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:20613 vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-42012 vdb-entry, x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2467441 issue-tracking, x_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:3.8.10-4.el10_2   < *
    cpe:/o:redhat:enterprise_linux:10.2
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   Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:3.6.16-8.el8_10.6   < *
    cpe:/a:redhat:enterprise_linux:8::appstream
    cpe:/o:redhat:enterprise_linux:8::baseos
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   Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:3.6.16-8.el8_10.6   < *
    cpe:/a:redhat:enterprise_linux:8::appstream
    cpe:/o:redhat:enterprise_linux:8::baseos
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   Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:3.8.10-4.el9_8   < *
    cpe:/a:redhat:enterprise_linux:9::appstream
    cpe:/o:redhat:enterprise_linux:9::baseos
Create a notification for this product.
   Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:3.8.10-4.el9_8   < *
    cpe:/a:redhat:enterprise_linux:9::appstream
    cpe:/o:redhat:enterprise_linux:9::baseos
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   Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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   Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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   Red Hat Red Hat Hardened Images     cpe:/a:redhat:hummingbird:1
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   Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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Show details on NVD website


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