CVE-2026-45126 LOW

CVE-2026-45126: MyBB: ACP Questions state CSRF

Vendor Mybb
Product mybb
Weakness CWE-352 · CSRF
Published August 18, 2026
Last update August 18, 2026

CVSS base score

3.5/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction Required
Confidentiality None
Integrity Low

CVSS vector

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

What the vulnerability does

01Description

MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP Security Questions module does not validate the anti-CSRF token correctly, allowing same-site attackers to enable or disable registration challenge questions with a specially crafted URL. The controller processes GET requests for the disable and enable actions to modify mybb_questions.active without verifying the my_post_key token attached by the user interface. The uniquely identifying implementation details include admin/modules/config/questions.php. This issue is fixed in version 1.8.40.

Key dates

02Disclosure timeline

August 18, 2026 CVE published

Related vulnerabilities

04Related CVE