CVE-2021-40509 Cross-site scripting in n/a

Medium 5.4 Published 4 Sep 2021 Updated 4 Aug 2024

Attackers can inject malicious scripts via user signatures in JForum2, potentially leading to session hijacking or code execution.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2021-40509?

CVE-2021-40509 is a medium-severity cross-site scripting vulnerability in n/a, published on 4 Sep 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

Official description

ViewCommon.java in JForum2 2.7.0 allows XSS via a user signature.

Weakness: CWE-79

Which versions are affected by CVE-2021-40509?

It affects 1 product.

Products include Jforum Jforum.

How do I fix CVE-2021-40509?

No fix has been published for CVE-2021-40509 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-2021-40509 being exploited?

There is no known exploitation of CVE-2021-40509 in the wild and no public exploit code.

Sources

Also known as GHSA-hfxg-ph49-2mw5.