Vulnerability · Published May 16, 2026 · Assigned by VulnCheck

CVE-2021-47934MyBB Timeline Plugin 1.0 Cross-Site Scripting and CSRF

Medium 5.3

In plain English

A medium-severity cross-site scripting in MyBB Timeline Plugin from MyBB. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities).

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)0.2%top 85.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

MyBB Timeline Plugin 1.0 contains cross-site scripting vulnerabilities that allow attackers to inject malicious scripts through thread titles, post content, and user profile fields like Location and Bio. Attackers can also exploit a cross-site request forgery vulnerability in the timeline.php profile action to change a user's cover picture by crafting malicious forms that execute when victims visit affected profiles.

Affected products (as reported)

Vendor	Product	Versions
MyBB	MyBB Timeline Plugin	1.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

References

ExploitDB-49467 exploit
Product Reference product
VulnCheck Advisory: MyBB Timeline Plugin 1.0 Cross-Site Scripting and CSRF third-party-advisory