TI-2026-08474 Aliases CVE-2026-9648 GHSA-7jx5-vvgh-vcjw

The crypton-x509-validation Haskell library fails to enforce X.509 NameConstraints…

MEDIUM 45Published 2026-06-11 · Updated 2026-06-11

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · High · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00223 12th percentileScored 2026-11-07

Fix Fixed crypton-certificate (Haskell Programming Language): 1.9.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Haskell Programming Language	crypton-certificate	before 1.9.1	1.9.1	Patch available	CNA

crypton-certificate VendorHaskell Programming Language Affected before 1.9.1 Fixed in 1.9.1 Patch available CNA

Remediation

Fix · CNA crypton-certificate (Haskell Programming Language) Fixed in 1.9.1

Timeline

2026-10-02 Threatist record created from CVE-2026-9648
2026-10-03 Alias added: GHSA-7jx5-vvgh-vcjw

References

Other 4

Sources

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