What the vulnerability does
01Description
The SlimStat Analytics plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'User-Agent' header in all versions up to, and including, 5.4.11 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 a user accesses an injected page. The show_complete_user_agent_tooltip setting must be explicitly enabled by an administrator (disabled by default) for the stored payload to be rendered and executed.
Explanation of Vulnerability in Simple Terms
02Summary
SlimStat Analytics versions 5.4.11 and earlier contain a cross-site scripting (XSS) vulnerability that allows attackers to inject malicious scripts into the application. The vulnerability can be exploited over the network without authentication or user interaction. Affected sites may serve malicious content to visitors or have their data modified.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that execute in visitors' browsers and modify site content or steal data.
Potential impact on your site
04Site Impact
Visitors may be redirected, have sessions hijacked, or see altered site content without your knowledge.
Conditions required to exploit
05Prerequisites
Network access to the site; no authentication or user interaction required.
Key dates
06Disclosure timeline
May 28, 2026
CVE published
May 28, 2026
Record updated
