PoC Index

CVE-2026-71417

HIGH 7.3EPSS 0.1%

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.

CVSS v3.1
7.3 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H
CVSS v3.1
7.3 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H
EPSS
0.08% chance of exploitation in the next 30 days, 0th percentile
Published
2026-08-18

Proof-of-concept exploits (1)

References

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