CVE-2025-54425

Workarounds

Workaround is to remove or reduce the time period of the output caching or to provide other restrictions to access the delivery API such as by IP.

References

Content delivery API documentation: https://docs.umbraco.com/umbraco-cms/reference/content-delivery-api

Umbraco's content delivery API can be restricted from public access such that an API key must be provided in a header to authorize the request.

It's also possible to configure output caching, such that the delivery API outputs will be cached for a period of time, improving performance.

There's an issue when these two things are used together though in that the caching doesn't vary by the header that contains the API key. As such it's possible for a user without a valid API key to retrieve a response for a given path and query if it has recently been requested and cached by request with a valid key.

CVE-2025-54425 has a CVSS score of 5.3 (Medium). The vector is network-reachable, no privileges required, and no user interaction. 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 (13.9.3, 15.4.4, 16.1.1); upgrading removes the vulnerable code path.

Kodem intelligence

Patches will be available in 13.9.3, 15.4.4 and 16.1.1.

1. What is CVE-2025-54425? CVE-2025-54425 is a medium-severity security vulnerability in Umbraco.Cms.Api.Delivery (nuget), affecting versions >= 13.0.0, <= 13.9.2. It is fixed in 13.9.3, 15.4.4, 16.1.1.
2. How severe is CVE-2025-54425? CVE-2025-54425 has a CVSS score of 5.3 (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 Umbraco.Cms.Api.Delivery are affected by CVE-2025-54425? Umbraco.Cms.Api.Delivery (nuget) versions >= 13.0.0, <= 13.9.2 is affected.
4. Is there a fix for CVE-2025-54425? Yes. CVE-2025-54425 is fixed in 13.9.3, 15.4.4, 16.1.1. Upgrade to this version or later.
5. Is CVE-2025-54425 exploitable, and should I be worried? Whether CVE-2025-54425 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-2025-54425 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-2025-54425?
   • Upgrade Umbraco.Cms.Api.Delivery to 13.9.3 or later
   • Upgrade Umbraco.Cms.Api.Delivery to 15.4.4 or later
   • Upgrade Umbraco.Cms.Api.Delivery to 16.1.1 or later