EUVD-2025-16778
GHSA-fr6r-p8hv-x3c4
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V5 - File Handling File type validation, storage isolation
MITRE ATT&CK
2 techniques across 2 tactics: Command and Control, Persistence The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | Remote code execution through uploaded web shells or malware, leading to complete server compromise. With a CVSS score of 5.5 (MEDIUM), this represents a moderate risk. |
| Exploit ScenarioDerived | An attacker uploads a PHP/JSP web shell disguised with a legitimate extension, then accesses it via the web server to execute arbitrary commands. |
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Alert meAnalysisAIv1 – Mar 14, 2026
Umbraco is an ASP.NET content management system (CMS). Starting in version 14.0.0 and prior to versions 15.4.2 and 16.0.0, it's possible to upload a file that doesn't adhere with the configured allowable file extensions via a manipulated API request. The issue is patched in versions 15.4.2 and 16.0.0. No known workarounds are available.
Earlier versions of this analysis (1)
RemediationAI
A vendor patch is available — apply it immediately. Validate file types by content (magic bytes), not just extension. Store uploads outside the web root. Use random filenames. Scan uploads for malware.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in nuget
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Unrestricted file upload allows attackers to upload malicious files (web shells, executables) that can then be executed on the server. This vulnerability is classified as Unrestricted Upload of File with Dangerous Type (CWE-434).
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
Lifecycle Timeline
2Executive ViewAI
Organizations using version 14.0.0 and should be aware of moderate risk from CVE-2025-48953, a unrestricted file upload vulnerability rated CVSS 5.5. This could allow unauthorized file access. A patch is available and should be applied during regular vulnerability management.
Apply vendor patch. If patching is delayed: restrict file access via WAF, implement allowlists.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Malicious file upload attacks exploit insufficient validation when web applications accept user-provided files.
Umbraco CMS versions prior to 4.7.1 are vulnerable to unauthenticated remote code execution via the codeEditorSave.asmx
The Page_Load function in Umbraco.Web/umbraco.presentation/umbraco/dashboard/FeedProxy.aspx.cs in Umbraco before 7.4.0 a
Umbraco Cloud 8.5.3 allows an authenticated file upload (and consequently Remote Code Execution) via the Install Package
Umbraco CMS v8.14.1 contains a server-side request forgery vulnerability that allows attackers to manipulate baseUrl par
A vulnerability was found in Umbraco CMS up to 10.7.7/12.3.6/13.5.2/14.3.1/15.1.1. Rated medium severity (CVSS 6.9), thi
A stored cross-site scripting (XSS) vulnerability in Umbraco CMS v14.3.1 allows attackers to execute arbitrary web scrip
An authenticated path traversal vulnerability exists during package installation in Umbraco CMS <= 8.9.1 or current, whi
Umbraco CMS 8.5.3 allows an authenticated file upload (and consequently Remote Code Execution) via the Install Package f
The FeedProxy.aspx script in Umbraco 4.7.0 allows remote attackers to proxy requests on their behalf via the "url" param
Multiple cross-site scripting (XSS) vulnerabilities in Umbraco before 7.4.0 allow remote attackers to inject arbitrary w
Arbitrary code execution in Umbraco CMS 16.3.3 is claimed via upload of a crafted PDF file that abuses insufficient file
File upload vulnerability in Umbraco Forms v.8.7.0 allows unauthenticated attackers to execute arbitrary code via a craf
Exploit-DB