# CVE-2025-48953: Umbraco Vulnerable to By-Pass of Configured Allowed Extensions for File Uploads

Source: https://junglewise.ai/threats/cve-2025-48953-umbraco-vulnerable-to-by-pass-of-configured-allowed-extensions  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-06-04  
License: CC BY 4.0 with a link back

CVE-2025-48953 · Severity: low · CVSS 3.1 · Published 2025-06-04

Umbraco Vulnerable to By-Pass of Configured Allowed Extensions for File Uploads

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

## Quick answers

**Is CVE-2025-48953 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-48953 being exploited in the wild.

**How severe is CVE-2025-48953?** Low severity, with a CVSS score of 3.1, published 4 June 2025.

**Which products and versions are affected?** Umbraco.Cms (NuGet) ECOSYSTEM:introduced=14.0.0,fixed=15.4.2.

**Is there a fix for CVE-2025-48953?** Yes. Umbraco.Cms (NuGet): upgrade to 15.4.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2025-48953?** Check whether you run Umbraco.Cms (NuGet) 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 15.4.2 or later

  ```sh
  dotnet add package Umbraco.Cms --version 15.4.2
  ```


## Affected products

- Umbraco.Cms (NuGet) ECOSYSTEM:introduced=14.0.0,fixed=15.4.2

## Identifiers

- CVE-2025-48953
- GHSA-fr6r-p8hv-x3c4

## 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)