CVE-2026-42013

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.

Affected Software

VendorProductVersion RangeStatus
Red HatRed Hat Enterprise Linux 100:3.8.10-4.el10_2 < *unaffected
Red HatRed Hat Enterprise Linux 10.0 Extended Update Support0:3.8.9-9.el10_0.19 < *unaffected
Red HatRed Hat Enterprise Linux 80:3.6.16-8.el8_10.6 < *unaffected
Red HatRed Hat Enterprise Linux 80:3.6.16-8.el8_10.6 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support0:3.6.14-10.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support0:4.13-3.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On0:3.6.14-10.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On0:4.13-3.el8_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support0:3.6.16-5.el8_6.5 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support0:4.13-3.el8_6.2 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On0:3.6.16-5.el8_6.5 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On0:4.13-3.el8_6.2 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Service0:3.6.16-7.el8_8.4 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Service0:4.13-4.el8_8.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutions0:3.6.16-7.el8_8.4 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutions0:4.13-4.el8_8.1 < *unaffected
Red HatRed Hat Enterprise Linux 90:3.8.10-4.el9_8 < *unaffected
Red HatRed Hat Enterprise Linux 90:3.8.10-4.el9_8 < *unaffected
Red HatRed Hat Enterprise Linux 9.4 Update Services for SAP Solutions0:3.8.3-4.el9_4.6 < *unaffected
Red HatRed Hat Enterprise Linux 9.6 Extended Update Support0:3.8.3-6.el9_6.4 < *unaffected
Red HatRed Hat Discovery 21782159791 < *unaffected
Red HatRed Hat Discovery 21782166952 < *unaffected
Red HatRed Hat Update Infrastructure 51781525684 < *unaffected
Red HatRed Hat Update Infrastructure 51781525671 < *unaffected
Red HatRed Hat Update Infrastructure 51781525693 < *unaffected
Red HatRed Hat Update Infrastructure 51781525739 < *unaffected

Weaknesses

  • CWE-295: Improper Certificate Validation

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References