Auth bypass in Netflix Lemur

CVE-2026-55163

Lemur manages TLS certificate creation. Prior to 1.9.2, PUT /api/1/roles/ in lemur/roles/views.py:298 authorized updates with RoleMemberPermission(role_id), which allowed either an administrator or any existing member of the target role. The handler passed data["users"] and data["name"] to service.update, allowing a non-admin member to add or remove other users and rename the role. This enabled lateral privilege grants within roles that control certificate and authority access and could deny access by removing legitimate members. The DELETE handler already required admin_permission, confirming that the weaker PUT authorization was inconsistent. The fix applies the same administrator-only requirement to the PUT handler. This issue is fixed in version 1.9.2.

Vulnerability class: Broken Access Control

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-55163?
CVE-2026-55163 is a medium-severity vulnerability in Netflix Lemur, classified under Incorrect Authorization. CVSS score: 6.3/10. Published 2026-08-18.
How severe is CVE-2026-55163?
Medium severity. CVSS v3 base score is 6.3 out of 10.