CVE-2026-45126

low
EUVD alias: EUVD-2026-61007
Assigned by CNA: github_m
Published 2026-08-18 · Modified 2026-08-18
CVSS v3
3.5
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
CVSS v4 NEW
not yet in upstream
VIR risk
3.5

Description

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.

Predictions

Exploit likelihood
45%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

References

CWEs

CWE-352

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.