PoC Index

CVE-2026-71308

HIGH 8.1EPSS 0.2%

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.

CVSS v3.1
8.1 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
CVSS v3.1
8.1 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
EPSS
0.18% chance of exploitation in the next 30 days, 7th percentile
Published
2026-08-18

Proof-of-concept exploits (1)

References

Related