Vulnerability Description
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.
CVSS Score
LOW
Related Weaknesses (CWE)
References
- https://github.com/mybb/mybb/commit/736a2bcbc7cc104df8ae6c0a160aa3917a1ceec0
- https://github.com/mybb/mybb/releases/tag/mybb_1840
- https://github.com/mybb/mybb/security/advisories/GHSA-m6hr-25cj-p58q
- https://mybb.com/versions/1.8.40
FAQ
What is CVE-2026-45128?
CVE-2026-45128 is a vulnerability with a CVSS score of 3.5 (LOW). 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 de...
How severe is CVE-2026-45128?
CVE-2026-45128 has been rated LOW with a CVSS base score of 3.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-45128?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.