CVE-2023-53978

5.1 mediumEPSS 0.2%

Medium (5.1) in mybb mybb. EPSS 0.2% chance of exploitation in the next 30 days.

myBB Forums 1.8.26 contains a stored cross-site scripting vulnerability in the forum announcement system that allows authenticated administrators to inject malicious scripts when creating announcements. Attackers can exploit this vulnerability by inserting script payloads in the announcement title field when adding announcements through the 'Forums and Posts' > 'Forum Announcements' interface, causing arbitrary JavaScript to execute when the announcement is displayed on the forum.

Severity

CVSS 4.0

5.1 medium

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

CVSS 3.1

5.4 medium

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS: 0.2% chance of exploitation in the next 30 days; higher than 14% of CVEs (scores of 2026-10-31)
CWE: CWE-79
Published: 2025-12-22
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

mybb:mybb

References

Check your stack JSON