Silverstripe CMS malicious file upload enables script execution
Silverstripe CMS through 4.5 can be susceptible to script execution from malicious upload contents under allowed file extensions (for example HTML code in a TXT file). When these files are stored as protected or draft files, the MIME detection can cause browsers to execute the file contents. Uploads stored as protected or draft files are allowed by default for authorised users only, but can also be enabled through custom logic as well as modules such as silverstripe/userforms. Sites using the previously optional silverstripe/mimevalidator module can configure MIME whitelists rather than extension whitelists, and hence prevent this issue. Sites on the Common Web Platform (CWP) use this module by default, and are not affected.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | silverstripe/cms | <= 4.5.0 | no fix |
References
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- Weakness (CWE)
CWE-434- Platform
- Composer
- Package
silverstripe/cms- Disclosed
- 24.05.2022
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-h77w-655f-6j3m - CC BY 4.0
Vulnerability history: silverstripe/cms
All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 16
- First → latest
- 11.2019 08.2026
- Without a fix
- 4
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 3
- Medium 11
- Low 1
Disclosures per year
- 2019: 1
- 2020: 0
- 2021: 0
- 2022: 11
- 2023: 0
- 2024: 3
- 2025: 0
- 2026: 1
-
Silverstripe CMS malicious file upload enables script execution this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.