ASP.NET CMS File Upload Vulnerability in Umbraco by Umbraco
CVE-2025-48953

5.5MEDIUM

Key Information:

Vendor

Umbraco

Status
Umbraco-cms
Vendor
CVE Published:
3 June 2025

What is CVE-2025-48953?

Umbraco, an ASP.NET content management system, has a vulnerability that allows unauthorized file uploads through manipulated API requests. This flaw impacts versions 14.0.0 and earlier, making it possible for attackers to bypass configured allowable file extensions, exposing the system to potential threats. Users are advised to update to versions 15.4.2 or 16.0.0 to mitigate the risk, as no workarounds are available for earlier versions.

Affected Version(s)

Umbraco-CMS >= 14.0.0, < 15.4.2

References

https://github.com/umbraco/Umbraco-CMS/security/advisorie...
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https://github.com/umbraco/Umbraco-CMS/commit/d920e93d1ee...
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CVSS V3.1

Score:
5.5
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
Low
User Interaction:
Required
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.
CVE-2025-48953 : ASP.NET CMS File Upload Vulnerability in Umbraco by Umbraco