XSS in Ubb Systems Ubb.threads

CVE-2026-54219

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.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

EPSS exploit prediction

EPSS: 0.004 (32.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 32.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-54219: held from 0.003 to 0.004.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

References