CVE-2026-45128 json
MyBB: ACP Users View Manager default CSRF
published 2mo ago modified 2mo ago also EUVD-2026-61050
- cvss
- 3.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 6%
- public exploits
- 0
- none known
Summary
MyBB is free and open source forum software. Prior to 1.8.40, the ACP Users View Manager module does not validate requests correctly, allowing same-site attackers to change a victim administrator's default user list view by embedding a specially crafted URL. The Set as Default control named set_default in Admin CP, Users & Groups, Users, View Manager changes the administrator's default view on GET requests without request forgery protection. The uniquely identifying implementation details include Users & Groups → Users → View Manager, and admin/inc/functions_view_manager.php. This issue is fixed in version 1.8.40.
Patch / fix
- mybb mybb 1.8.40
Is CVE-2026-45128 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N |
Affected products
- mybb mybb
Classification
- Weakness
-
- CWE-352 Cross-Site Request Forgery
References
Sources
- CVE List CVE-2026-45128
- NVD CVE-2026-45128
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.