CVE-2025-61788

Prior to Opencast 17.8 and 18.2 the paella would include and render some user inputs (metadata like title, description, etc.) unfiltered and unmodified.

Resources

• Patch fixing the issue

For more information

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• Open an issue in our issue tracker
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The vulnerability allows attackers to inject and malicious HTML and JavaScript in the player, which would then be executed in the browsers of users watching the prepared media. This can then be used to modify the site or to execute actions in the name of logged-in users.

To inject malicious metadata, an attacker needs write access to the system. For example, the ability to upload media and modify metadata. This cannot be exploited by unauthenticated users.

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-2025-61788 has a CVSS score of 5.4 (Medium). The vector is network-reachable, low 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. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.

Kodem intelligence

This issue is fixed in Opencast 17.8 and 18.2, however they are not published to the Maven registry.

1. What is CVE-2025-61788? CVE-2025-61788 is a medium-severity cross-site scripting (XSS) vulnerability in org.opencastproject:opencast-common (maven), affecting versions <= 16.10. No fixed version is listed yet. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2025-61788? CVE-2025-61788 has a CVSS score of 5.4 (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 org.opencastproject:opencast-common are affected by CVE-2025-61788? org.opencastproject:opencast-common (maven) versions <= 16.10 is affected.
4. Is there a fix for CVE-2025-61788? No fixed version is listed for CVE-2025-61788 yet. Monitor the advisory for updates and apply mitigations in the interim.
5. Is CVE-2025-61788 exploitable, and should I be worried? Whether CVE-2025-61788 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-2025-61788 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-2025-61788? No fixed version is listed yet. In the interim: Validate and encode untrusted input before rendering it as HTML. Applying a Content Security Policy reduces the impact if encoding is bypassed.