CVE-2026-45121 (GCVE-0-2026-45121)
Vulnerability from cvelistv5
Published
2026-08-18 15:45
Modified
2026-08-18 18:50
CWE
  • CWE-863 - Incorrect Authorization
Summary
MyBB is free and open source forum software. Prior to 1.8.40, the calendar module does not check permissions consistently when listing calendars, allowing authenticated users to access titles of calendars that are otherwise inaccessible. The affected calendar-selection paths in calendar.php perform permission checks against an invalid calendar context before returning calendar titles. The uniquely identifying implementation details include titles of inaccessible calendars, and invalid calendar permission context. This issue is fixed in version 1.8.40.
Impacted products
Vendor Product Version
mybb mybb Version: < 1.8.40
Create a notification for this product.
Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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