CVE-2026-42562 HIGH

CVE-2026-42562: Plainpad: Privilege Escalation via Writable Admin Field in Profile Update (Access Control)

Vendor Alextselegidis
Product plainpad
Weakness CWE-269
Published May 9, 2026
Last update May 11, 2026

CVSS base score

8.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

May 9, 2026 CVE published
May 11, 2026 Record updated