CVE-2026-54219 Stored XSS in UBB.threads
Attackers can inject malicious JavaScript into user posts or profiles, executing code in victims' browsers to potentially hijack accounts.
- 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-2026-54219?
CVE-2026-54219 is a medium-severity cross-site scripting vulnerability in UBB.threads, published on 18 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
UBB.threads is vulnerable to Stored XSS via user posts and user profile fields. The application fails to properly sanitize user input, allowing low privileged attackers to inject arbitrary JavaScript that executes in a victim's browser upon viewing.
Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 7.7.5 but may also affect other versions.
Weakness: CWE-79
Which versions are affected by CVE-2026-54219?
How do I fix CVE-2026-54219?
No fix has been published for CVE-2026-54219 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-2026-54219 being exploited?
There is no known exploitation of CVE-2026-54219 in the wild and no public exploit code.
Sources
Also known as GHSA-mxqw-8v8m-qpmf.