CVE-2026-27137 (GCVE-0-2026-27137)

Vulnerability from cvelistv5 – Published: 2026-03-06 21:28 – Updated: 2026-03-10 13:32
VLAI
Title
Incorrect enforcement of email constraints in crypto/x509
Summary
When verifying a certificate chain which contains a certificate containing multiple email address constraints which share common local portions but different domain portions, these constraints will not be properly applied, and only the last constraint will be considered.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-295 - Improper Certificate Validation
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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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • 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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