CVE-2023-53978 MEDIUM

CVE-2023-53978: myBB Forums 1.8.26 Stored Cross-Site Scripting via Forum Announcements

Vendor Mybb

Product myBB forums

Weakness CWE-79 · XSS

Published December 22, 2025

Last update April 7, 2026

View on NVD All CVEs

CVSS base score

5.1/10

Attack vector Network

Attack complexity Low

Privileges required Low

User interaction —

Confidentiality —

Integrity —

CVSS vector

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

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

December 22, 2025 CVE published

April 7, 2026 Record updated

External resources

03References

NVD — National Vulnerability Database https://nvd.nist.gov/vuln/detail/CVE-2023-53978 CWE — Common Weakness Enumeration https://cwe.mitre.org/data/definitions/79.html