CVE-2025-54425 is a medium-severity (CVSS 5.3) Information Exposure vulnerability in Umbraco.Cms.Api.Delivery. A fix is available for Umbraco.Cms.Api.Delivery — see the affected versions and patch details below.
Umbraco's Delivery API allows for cached requests to be returned with an invalid API key
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-54425.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2025-54425 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
Umbraco.Cms.Api.Delivery.NETUmbraco.Cms.Api.Delivery.NETUmbraco.Cms.Api.DeliveryReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Impact
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.
Patches
Patches will be available in 13.9.3, 15.4.4 and 16.1.1.
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
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | Umbraco.Cms.Api.Delivery | ≥ 13.0.0&&< 13.9.3 | 13.9.3dotnet add package Umbraco.Cms.Api.Delivery --version 13.9.3 |
| .NETNuGet | Umbraco.Cms.Api.Delivery | ≥ 15.0.0&&< 15.4.4 | 15.4.4dotnet add package Umbraco.Cms.Api.Delivery --version 15.4.4 |
| .NETNuGet | Umbraco.Cms.Api.Delivery | ≥ 16.0.0&&< 16.1.1 | 16.1.1dotnet add package Umbraco.Cms.Api.Delivery --version 16.1.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Umbraco.Cms.Api.Delivery, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Umbraco.Cms.Api.Delivery to 13.9.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-54425 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-54425 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-54425. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-54425 in your dependencies?
O3 Security finds CVE-2025-54425 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.