CVE-2025-67288: n/a
An arbitrary file upload vulnerability in Umbraco CMS v16.3.3 allows attackers to execute arbitrary code by uploading a crafted PDF file. NOTE: this is disputed by the Supplier because the responsibility for file validation (as shown in the documentation) belongs to the system administrator who is implementing Umbraco CMS in their environment, not to Umbraco CMS itself. The Supplier also states that PDF JavaScript runs in a completely isolated sandbox, not the browser's DOM context, which means that privilege boundaries would not be crossed, a related issue to CVE-2023-49279.
AI Analysis
Technical Summary
CVE-2025-67288 describes an arbitrary file upload vulnerability in Umbraco CMS version 16.3.3. The reported issue allows attackers to upload a specially crafted PDF file that could lead to arbitrary code execution. However, the vendor disputes the claim, emphasizing that file validation is the responsibility of the system administrator implementing Umbraco CMS, not the CMS itself. Additionally, the vendor notes that PDF JavaScript runs in a sandbox isolated from the browser DOM, which should prevent privilege boundary crossing. This vulnerability is related to CWE-434 (Unrestricted Upload of File with Dangerous Type) and is linked conceptually to CVE-2023-49279. No patch or official fix information is provided.
Potential Impact
If exploitable, this vulnerability could allow remote attackers to execute arbitrary code on systems running Umbraco CMS version 16.3.3 by uploading malicious PDF files. This could lead to full system compromise, data loss, or service disruption. However, the vendor disputes the vulnerability's validity and states that the PDF JavaScript runs in a sandboxed environment, limiting impact. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. The vendor states that file validation is the responsibility of the system administrator deploying Umbraco CMS. Administrators should ensure strict file upload validation and sandboxing controls are in place. Monitor vendor channels for any official fixes or updates regarding this vulnerability.
CVE-2025-67288: n/a
Description
An arbitrary file upload vulnerability in Umbraco CMS v16.3.3 allows attackers to execute arbitrary code by uploading a crafted PDF file. NOTE: this is disputed by the Supplier because the responsibility for file validation (as shown in the documentation) belongs to the system administrator who is implementing Umbraco CMS in their environment, not to Umbraco CMS itself. The Supplier also states that PDF JavaScript runs in a completely isolated sandbox, not the browser's DOM context, which means that privilege boundaries would not be crossed, a related issue to CVE-2023-49279.
CVSS v3.1
Score 10.0critical
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-67288 describes an arbitrary file upload vulnerability in Umbraco CMS version 16.3.3. The reported issue allows attackers to upload a specially crafted PDF file that could lead to arbitrary code execution. However, the vendor disputes the claim, emphasizing that file validation is the responsibility of the system administrator implementing Umbraco CMS, not the CMS itself. Additionally, the vendor notes that PDF JavaScript runs in a sandbox isolated from the browser DOM, which should prevent privilege boundary crossing. This vulnerability is related to CWE-434 (Unrestricted Upload of File with Dangerous Type) and is linked conceptually to CVE-2023-49279. No patch or official fix information is provided.
Potential Impact
If exploitable, this vulnerability could allow remote attackers to execute arbitrary code on systems running Umbraco CMS version 16.3.3 by uploading malicious PDF files. This could lead to full system compromise, data loss, or service disruption. However, the vendor disputes the vulnerability's validity and states that the PDF JavaScript runs in a sandboxed environment, limiting impact. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. The vendor states that file validation is the responsibility of the system administrator deploying Umbraco CMS. Administrators should ensure strict file upload validation and sandboxing controls are in place. Monitor vendor channels for any official fixes or updates regarding this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2025-12-08T00:00:00.000Z
- Cvss Version
- null
- State
- PUBLISHED
Threat ID: 69498ef9c525bff625d87afc
Added to database: 12/22/2025, 18:33:29 UTC
Last enriched: 07/13/2026, 08:37:20 UTC
Last updated: 08/24/2026, 10:52:06 UTC
Views: 472
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