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.
History

Tue, 18 Aug 2026 20:45:00 +0000

Type Values Removed Values Added
First Time appeared Netflix
Netflix lemur
Vendors & Products Netflix
Netflix lemur

Tue, 18 Aug 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 18 Aug 2026 19:30:00 +0000

Type Values Removed Values Added
Description 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.
Title Lemur: Unchecked `replaces[]` lets any user silence notifications and hijack auto-rotation for arbitrary certificates
Weaknesses CWE-639
CWE-862
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-18T19:34:59.015Z

Reserved: 2026-08-05T18:14:42.063Z

Link: CVE-2026-71308

cve-icon Vulnrichment

Updated: 2026-08-18T19:34:54.490Z

cve-icon NVD

Status : Received

Published: 2026-08-18T20:17:23.740

Modified: 2026-08-18T20:17:23.740

Link: CVE-2026-71308

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-18T20:45:04Z