CVE-2025-54425: Umbraco is an ASP.NET CMS. In versions 13.0.0 through 13.9.2, 15.0.0 through 15.4.1 and 16.0.0 through 16.1.0, the content delivery API can be restric...

Description

Umbraco is an ASP.NET CMS. In versions 13.0.0 through 13.9.2, 15.0.0 through 15.4.1 and 16.0.0 through 16.1.0, the content delivery API can be restricted from public access where 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, where 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. This is fixed in versions 13.9.3, 15.4.4 and 16.1.1.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Probability

0.31%

22.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-200

Affected Software

Vendor	Product	Versions
Umbraco	Umbraco Cms	>= 13.0.0, < 13.9.3
Umbraco	Umbraco Cms	>= 15.0.0, < 15.4.4
Umbraco	Umbraco Cms	>= 16.0.0, < 16.1.1

References

Timeline

Published: Jul 30, 2025
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2025-54425?

Umbraco is an ASP.NET CMS. In versions 13.0.0 through 13.9.2, 15.0.0 through 15.4.1 and 16.0.0 through 16.1.0, the content delivery API can be restricted from public access where 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, where 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. This is fixed in versions 13.9.3, 15.4.4 and 16.1.1.

How severe is CVE-2025-54425?

CVE-2025-54425 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.31% probability of exploitation in the next 30 days.

How do I fix CVE-2025-54425?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.