CVE-2025-27412

Reflected cross-site scripting (XSS) is a type of web vulnerability that occurs when a web application fails to properly sanitize user input, allowing an attacker to inject malicious code into the application's response to a user's request. When the user's browser receives the response, the malicious code is executed, potentially allowing the attacker to steal sensitive information or take control of the user's account.

Details

On the latest version of Redaxo, v5.18.2, the rex-api-result parameter is vulnerable to Reflected cross-site scripting (XSS) on the page of AddOns.

PoC

1. Login Redaxo as administrative user.
2. Navigate to the URL: http://localhost/redaxo/index.php?page=packages&rex-api-call=package&&rex-api-result={%22succeeded%22%3Atrue%2C%22message%22%3A%22%3Cimg%20src=x%20onerror=alert(document.domain);%3E%22}, the XSS executes.

This can lead to various security risks, including session hijacking, phishing attacks and malware distribution. History page visible to administrative user and when an administrator views the infected page, the attacker may gain elevated privileges, further compromising the system.

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

CVE-2025-27412 has a CVSS score of 6.1 (Medium). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.18.3); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2025-27412? CVE-2025-27412 is a medium-severity cross-site scripting (XSS) vulnerability in redaxo/source (composer), affecting versions >= 5.0.0, < 5.18.3. It is fixed in 5.18.3. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2025-27412? CVE-2025-27412 has a CVSS score of 6.1 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of redaxo/source are affected by CVE-2025-27412? redaxo/source (composer) versions >= 5.0.0, < 5.18.3 is affected.
4. Is there a fix for CVE-2025-27412? Yes. CVE-2025-27412 is fixed in 5.18.3. Upgrade to this version or later.
5. Is CVE-2025-27412 exploitable, and should I be worried? Whether CVE-2025-27412 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2025-27412 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2025-27412? Upgrade redaxo/source to 5.18.3 or later.