CVE-2017-15280 is a medium-severity (CVSS 5.5) XML External Entity (XXE) vulnerability in UmbracoCms.Web. A fix is available for UmbracoCms.Web — see the affected versions and patch details below.
Umbraco CMS XXE Vulnerability
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
UmbracoCms.WebReal-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
XML external entity (XXE) vulnerability in Umbraco CMS before 7.7.3 allows attackers to obtain sensitive information by reading files on the server or sending TCP requests to intranet hosts (aka SSRF), related to Umbraco.Web/umbraco.presentation/umbraco/dialogs/importDocumenttype.aspx.cs.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | UmbracoCms.Web | all versions | 7.7.3dotnet add package UmbracoCms.Web --version 7.7.3 |
Affected Products
umbraco cmsumbracoDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for UmbracoCms.Web, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update UmbracoCms.Web to 7.7.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2017-15280 is resolved across your whole dependency graph.
Workarounds
Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.
Frequently Asked Questions
Is CVE-2017-15280 in your dependencies?
Find it across NuGet, including transitive dependencies.