CVE-2026-71417
HighCVSS 7.3Exploitation Probability (EPSS)
Low risk0th percentile - higher than 0% of all known CVEs
Summary
Lemur before version 1.9.3 contains a vulnerability in API endpoints that allows an unprivileged user to create a duplicate certificate without required permissions and then revoke it, potentially leading to denial of service for all certificates. The fix in version 1.9.3 rejects duplicates and requires authority access.
Risk Assessment
The risk includes the ability to revoke arbitrary certificates, potentially causing TLS service disruptions across the infrastructure.
Recommendation
Upgrade Lemur to version 1.9.3 or later, which includes the fix for this vulnerability.
Original NVD description (English source)
Lemur manages TLS certificate creation. Prior to 1.9.3, POST /api/1/certificates/upload allowed a non-read-only user to create a duplicate row using another certificate body, authority_id, serial, or external_id without requiring permission on the underlying authority. PUT /api/1/certificates//revoke authorized the caller against only the selected Lemur row, so the creator of the duplicate bypassed CertificatePermission. The duplicate had no cert.endpoints, which also bypassed the safeguard that prevents revocation of deployed certificates. Issuer plugins then revoked the real CA-side certificate using certificate.body or external_id under the stored authority credentials. An attacker could therefore revoke arbitrary managed certificates and cause fleet-wide TLS denial of service. The fix rejects duplicate authority_id and serial identities, requires authority access on upload, and checks every matching row during revocation. This issue is fixed in version 1.9.3.