CVE-2026-9648

CRITICAL EPSS 12.8%
Published Jun 11, 20262w ago · Modified Jun 17, 20261w ago
9.1 CVSS 3.1
Critical
Find Similar
Published Jun 11, 2026 2w ago
Last Modified Jun 17, 2026 1w ago

Description

The crypton-x509-validation Haskell library fails to enforce X.509 NameConstraints, allowing TLS clients to accept certificates whose Subject Alternative Names fall outside the issuing CA’s permitted subtrees. This oversight enables an attacker who compromises a name-constrained sub-CA to impersonate domains beyond its intended scope.

CVSS Details

Base Score
9.1
Exploitability
3.9
Impact
5.2
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability None

Threat Intelligence

EPSS Exploit Probability
12.8% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

References 5

  • github.com https://github.com/haskell/security-advisories/pull/332
  • github.com https://github.com/kazu-yamamoto/crypton-certificate/pull/30
  • github.com https://github.com/kazu-yamamoto/crypton-certificate/pull/30/changes/f4b77edf6ead77f4a886da40e41eab20f0180e39
  • hackage.haskell.org https://hackage.haskell.org/package/crypton-x509-validation-1.9.1/revisions/
  • kb.cert.org https://www.kb.cert.org/vuls/id/862559

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.