CVE-2026-42013 (GCVE-0-2026-42013)
Vulnerability from cvelistv5
Published
2026-05-26 21:29
Modified
2026-06-02 15:34
CWE
  • CWE-1284 - Improper Validation of Specified Quantity in Input
Summary
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.
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-2026-42013 vdb-entry, x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2467448 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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