# CVE-2025-66625: Umbraco Vulnerable to Improper File Access and Credential Exposure in Dictionary Import Functionality

Source: https://junglewise.ai/threats/cve-2025-66625-umbraco-vulnerable-to-improper-file-access-and-credential  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-12-09  
License: CC BY 4.0 with a link back

CVE-2025-66625 · Severity: medium · CVSS 4.9 · Published 2025-12-09

Umbraco is an ASP.NET CMS. Due to unsafe handling and deletion of temporary files in versions 10.0.0 through 13.12.0, during the dictionary upload process an attacker with access to the backoffice can trigger predictable requests to temporary file paths. The application’s error responses (HTTP 500 when a file exists, 404 when it does not) allow the attacker to enumerate the existence of arbitrary files on the server’s filesystem. This vulnerability does not allow reading or writing file contents. In certain configurations, incomplete clean-up of temporary upload files may additionally expose the NTLM hash of the Windows account running the Umbraco application. This issue is fixed in version 13.12.1.

Technologies: [Umbraco.Cms (NuGet)](https://junglewise.ai/threats/technologies/umbraco-cms), [Umbraco Cms](https://junglewise.ai/threats/technologies/umbraco-cms-1). Vendors: [NuGet](https://junglewise.ai/threats/vendors/nuget), [Umbraco](https://junglewise.ai/threats/vendors/umbraco).

## Quick answers

**Is CVE-2025-66625 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-66625 being exploited in the wild.

**How severe is CVE-2025-66625?** Medium severity, with a CVSS score of 4.9, published 9 December 2025.

**Which products and versions are affected?** Umbraco.Cms (NuGet) ECOSYSTEM:introduced=10.0.0,fixed=13.12.1.

**Is there a fix for CVE-2025-66625?** Yes. Umbraco.Cms (NuGet): upgrade to 13.12.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2025-66625?** Check whether you run Umbraco.Cms (NuGet) or Umbraco Cms at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Umbraco.Cms (NuGet): upgrade to 13.12.1 or later

  ```sh
  dotnet add package Umbraco.Cms --version 13.12.1
  ```


## Affected products

- Umbraco.Cms (NuGet) ECOSYSTEM:introduced=10.0.0,fixed=13.12.1
- Umbraco Cms

## Identifiers

- CVE-2025-66625
- GHSA-hfv2-pf68-m33x

## Related threats

- [Umbraco Delivery API authorization bypass in content reference expansion](https://junglewise.ai/threats/cve-2026-69197-umbraco-delivery-api-authorization-bypass-in-content-reference)
- [Umbraco CMS open redirect in member Surface Controllers](https://junglewise.ai/threats/cve-2026-46616-umbraco-cms-open-redirect-in-member-surface-controllers)
- [Umbraco CMS HTML injection in Backoffice confirmation dialog](https://junglewise.ai/threats/cve-2026-46609-umbraco-cms-html-injection-in-backoffice-confirmation-dialog)
- [Umbraco Affected by Vertical Privilege Escalation via Missing Authorization Checks](https://junglewise.ai/threats/cve-2026-31834-umbraco-affected-by-vertical-privilege-escalation-via-missing)
- [Umbraco has Stored XSS in UFM Rendering Pipeline via Permissive DOMPurify Attribute Filtering](https://junglewise.ai/threats/cve-2026-31833-umbraco-has-stored-xss-in-ufm-rendering-pipeline-via-permissive)