CVE detail
CVE-2026-45122
MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not validate moderation permissions for the destination calendar when moving events. A user with moderation permission for the source calendar can move an event to a calendar where the user has only viewing permission because the do_move action in calendar.php does not check canmoderateevents for the target calendar. The uniquely identifying implementation details include calendar event move, source calendar moderation permission, and destination calendar viewing permission. This issue is fixed in version 1.8.40.
Buzz score
Why this CVE is surfacing
This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.
Buzz score components · mention 16.1 · diversity 10.0 · KEV 0.0 · OTX 0.0 · PoC 0.0
Why it matters now
Mention timeline
- Total mentions
- 4
- within the 30d window
- Peak daily
- 4
- highest bucket
Evidence
Source links by recency
4 source links · newest first
- https://mybb.com/versions/1.8.40mybb.com
No excerpt available.
Release Notesmybb.comAug 18, 2026, 4:17 PM No excerpt available.
Exploitgithub.comAug 18, 2026, 4:17 PMNo excerpt available.
Exploitgithub.comAug 18, 2026, 4:17 PMNo excerpt available.
Exploitgithub.comAug 18, 2026, 4:17 PM
Exploit code
Public exploit repository references
Public PoC repositories are third-party, potentially unsafe artifacts. Treat their code as untrusted and use it only on authorized systems in an isolated, least-privilege environment. cvebuzz does not execute the code or verify that an exploit works.
0 repository references · best confidence N/A · max 0 stars
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