CVE-2026-71308 — Lemur: Unchecked `replaces[]` lets any user silence notifications and hijack auto-rotation for arbitrary certificates

Description (CNA)

Lemur manages TLS certificate creation. From 0.5.0 until 1.9.3, certificate create, upload, and edit requests accepted replaces[] or replacements identifiers that AssociatedCertificateSchema resolved with fetch_objects without a CertificatePermission check. Assigning those objects to Certificate.replaces invoked an append listener that disabled the victim certificate notifications and marked it as replaced. The victim was then excluded from get_all_pending_reissue, and certificate_rotate could deploy the attacker certificate to endpoints serving the victim. An authenticated non-read-only user could target certificates for which the user had no ownership or role, suppress lifecycle automation, and cause fleet-wide TLS disruption or unauthorized substitution. The fix authorizes every referenced replacement certificate before mutation. This issue is fixed in version 1.9.3.

Affected (CNA)

Vendor / product	Versions
Netflix / lemur	affected >= 0.5.0, < 1.9.3

CWE

CWE-639, CWE-862

References

ADP enrichment

CISA-ADP

No English description supplied.

https://github.com/Netflix/lemur/security/advisories/GHSA-cfh6-pv5c-38jv