CVE-2026-54221
Deferred Deferred - Pending Action

Reflected Cross-Site Scripting in UBB.threads

Publication date: 2026-06-18

Last updated on: 2026-06-18

Assigner: CERT.PL

Description
UBB.threads is vulnerable to Reflected XSS. The application improperly handles user input in certain requests, enabling attackers to execute arbitrary JavaScript in the context of a victim's browser by tricking them into clicking a crafted link.  Because vendor contact attempts were unsuccessful, the vulnerability has only been confirmed in version 7.7.5 but may also affect other versions.

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Meta Information

Published
2026-06-18
Last Modified
2026-06-18
Generated
2026-07-09
AI Q&A
2026-06-18
EPSS Evaluated
2026-07-08
NVD
CVE-2026-54221
EUVD
EUVD-2026-37884

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
ubbt ubbt_threads to 7.7.5 (inc)

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Exploitability

CWE
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KEV
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CWE ID Description
CWE-79 The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

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Impact Analysis

This vulnerability can allow attackers to execute arbitrary JavaScript in your browser, potentially leading to session hijacking, theft of sensitive information, or performing actions on your behalf without your consent. It relies on tricking users into clicking malicious links, which can compromise the security and privacy of affected users.

Executive Summary

UBB.threads is vulnerable to Reflected Cross-Site Scripting (XSS). This means the application does not properly handle user input in certain requests, allowing attackers to inject and execute arbitrary JavaScript code in the victim's browser. The attacker can trick a user into clicking a specially crafted link, which then executes malicious scripts in the context of the user's session.

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