CVE-2021-47934 MyBB Timeline Plugin 1.0 Cross-Site Scripting and CSRF
Attackers can inject malicious scripts via user inputs or force profile changes via CSRF in the MyBB Timeline Plugin, potentially compromising user accounts.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-47934?
CVE-2021-47934 is a medium-severity cross-site scripting vulnerability in MyBB Timeline Plugin, published on 16 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
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.
Weakness: CWE-79
Which versions are affected by CVE-2021-47934?
How do I fix CVE-2021-47934?
No fix has been published for CVE-2021-47934 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2021-47934 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47934 exists.
Sources
Also known as GHSA-9cv3-xr79-r4jw.