CVE-2026-27138 (GCVE-0-2026-27138)

Vulnerability from cvelistv5 – Published: 2026-03-06 21:28 – Updated: 2026-03-10 13:35
VLAI
Title
Panic in name constraint checking for malformed certificates in crypto/x509
Summary
Certificate verification can panic when a certificate in the chain has an empty DNS name and another certificate in the chain has excluded name constraints. This can crash programs that are either directly verifying X.509 certificate chains, or those that use TLS.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-10 13:34 UTC
CWE
  • CWE-1285 - Improper Validation of Specified Index, Position, or Offset in Input
Assigner
Go
References
Impacted products
Vendor Product Version
Go standard library crypto/x509 Affected: 1.26.0-0 , < 1.26.1 (semver)
Create a notification for this product.
Credits
Jakub Ciolek
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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