CVE-2026-71317mediumCWE-862

CVE-2026-71317: medium-severity vulnerability in Netflix lemur

Lemur: Sub-CA creation never checks `AuthorityPermission` on the parent authority

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 0.1%
Lemur manages TLS certificate creation. Prior to 1.9.3, POST /api/1/authorities with type=subca did not require AuthorityPermission on the parent authority when ADMIN_ONLY_AUTHORITY_CREATION was false. AssociatedAuthoritySchema resolved the caller-supplied parent and passed it through authority creation to cryptography-issuer, which used the parent authority_certificate.private_key to sign a new intermediate. Any authenticated non-read-only user in that supported configuration could chain a sub-CA to an internal root for which the user held no role. The resulting intermediate could issue trusted certificates and its private key could be used outside Lemur, bypassing normal issuance controls. The fix checks AuthorityPermission on every supplied parent before invoking the issuer. This issue is fixed in version 1.9.3.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
Affected products
Netflix · lemur
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