CVE-2026-45126
MyBB: ACP Questions state CSRF
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Low3.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Low3.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.17% · top 93% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.5.
Weakness
Affected products
References (4)
- https://github.com/mybb/mybb/security/advisories/GHSA-m42q-vgx3-fqcc (opens in a new tab)x_refsource_CONFIRM
- https://github.com/mybb/mybb/commit/6893b395c7fa3b9e4de6235caea0ce198c376c4f (opens in a new tab)x_refsource_MISC
- https://github.com/mybb/mybb/releases/tag/mybb_1840 (opens in a new tab)x_refsource_MISC
- https://mybb.com/versions/1.8.40 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-45126)Record last updated .