CVE-2026-45120

MyBB: Insufficient authorization for private calendar events

State
Published
Severity
5.4 Medium
Published
Aug 18, 2026
Updated
Aug 18, 2026
Reserved
May 8, 2026

Read the record on cve.org

Description

MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not verify private event status consistently, allowing users with viewing and moderation permissions to access and moderate private events. The private-event check used by get_events() in inc/functions_calendar.php and the event action is missing from the remaining calendar.php actions, despite the limited-access behavior described in inc/languages/english/calendar.lang.php. This issue is fixed in version 1.8.40.

Scores

CVSSScoreVectorSource
3.15.4 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:NGitHub_M

Weaknesses

  • CWE-639 Authorization Bypass Through User-Controlled Key

Affected Products

ProductVersions
mybbmybb
  • < 1.8.40Affected

References

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