PT-2026-39406 · Alextselegidis · Plainpad

Published 2026-05-09 · Updated 2026-05-09 · CVE-2026-42562

Mitre

CVSS v3.1

8.3

High

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L

Plainpad is a self hosted note taking app. Prior to version 1.1.1, Plainpad allows a low-privilege authenticated user to self-escalate to administrator by submitting admin=true in PUT /api.php/v1/users/{id}. The endpoint directly persists the admin attribute from user input, and the escalated account can immediately access admin-only routes. This issue has been patched in version 1.1.1.

Fix

Improper Privilege Management

Weakness Enumeration

CWE-269

Related Identifiers

CVE-2026-42562

Affected Products

Plainpad

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-42562 · Security Note
• https://github.com/alextselegidis/plainpad/releases/tag/1.1.1 · Note
• https://github.com/alextselegidis/plainpad/commit/9216a876d27b22c3d9259551636d803f7cb075fc · Note
• https://github.com/alextselegidis/plainpad/security/advisories/GHSA-pvfv-wvpm-q6f6 · Note
• https://github.com/alextselegidis/plainpad/issues/138 · Note