CVE-2026-115548

Quttera ThreatSign <= 4.1.0.48 - Unauthenticated Stored Cross-Site Scripting via User-Agent Header

Published 7 Nov 2026 • Updated 7 Nov 2026

Severity: HIGH

Description

The Quttera ThreatSign – Web Malware Scanner for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'HTTP_USER_AGENT' parameter in all versions up to, and including, 4.1.0.48 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever an administrator accesses an injected page.

Affected products (1)

• quttera Quttera ThreatSign – Web Malware Scanner for WordPress

Problem types

• CWE-79 Improper Neutralization of Input During Web Page Generation

References (6)

• https://www.wordfence.com/threat-intel/vulnerabilities/id/eacc5af0-3248-4819-b90e-0f5e0e6d2786?source=cve
• https://plugins.trac.wordpress.org/browser/quttera-web-malware-scanner/tags/4.1.0.45/qtrAjaxHandler.php#L1199
• https://plugins.trac.wordpress.org/browser/quttera-web-malware-scanner/tags/4.1.0.45/JS/iscan_frontend.php#L112
• https://plugins.trac.wordpress.org/browser/quttera-web-malware-scanner/tags/4.1.0.45/qtrDatabaseScanner.php#L345
• https://plugins.trac.wordpress.org/browser/quttera-web-malware-scanner/tags/4.1.0.45/qtrReport.php#L133
• https://plugins.trac.wordpress.org/changeset?reponame=&old=3771915%40quttera-web-malware-scanner&new=3771915%40quttera-web-malware-scanner