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TI-2026-50046 Aliases CVE-2026-71417GHSA-pxmc-2ffp-8j67

Lemur: Any user can revoke arbitrary certificates at the CA by uploading a duplicate record and revoking it

Priority HIGH 65CWE-639Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-639.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00105 1st percentileScored 2026-11-07
Fix Fixed lemur (Netflix): 1.9.3lemur (PyPI): 1.9.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Netflixlemurbefore 1.9.31.9.3Patch availableCNA
—lemur (PyPI)before 1.9.31.9.3Patch availableGHSA-pxmc-2ffp-8j67
  • lemur VendorNetflix Affected before 1.9.3 Fixed in 1.9.3 Patch available CNA
  • lemur (PyPI) Vendor— Affected before 1.9.3 Fixed in 1.9.3 Patch available GHSA-pxmc-2ffp-8j67

Remediation

  • Fix · CNA lemur (Netflix) Fixed in 1.9.3
  • Fix · GHSA-pxmc-2ffp-8j67 lemur (PyPI) Fixed in 1.9.3 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-71417
  2. 2026-10-03 Alias added: GHSA-pxmc-2ffp-8j67

References

Other 4

  • TI-2024-04374 Path Traversal vulnerability via File Uploads in Genie CVSS 3.1CRITICAL 9.9
  • TI-2023-21044 Dispatch writes JWT tokens in error message CVSS 3.1CRITICAL 9.1
  • TI-2026-39854 Improper authorization in Netflix lemur CVSS 3.1CRITICAL 9.9
  • TI-2026-32272 Lemur: LDAP Filter Injection enables post-authentication privilege escalation CVSS 3.1HIGH 8.1
  • TI-2026-49966 Lemur: Unchecked `replaces[]` lets any user silence notifications and hijack auto-rotation for arbitrary certificates CVSS 3.1HIGH 8.1
  • TI-2026-49965 Missing authorization in Netflix lemur CVSS 3.1HIGH 7.7
See all 33 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences