Vulnerability · Published Jul 15, 2020 · Assigned by mitre
CVE-2020-9309
High 8.8
In plain English
A high-severity security flaw in the silverstripe/cms package (Packagist). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.8% (higher than 79% of all known vulnerabilities).
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Packagist | silverstripe/cms | no fix listed | GHSA-h77w-655f-6j3m |
Affected products (as reported)
References
- https://www.silverstripe.org/download/security-releases/CVE-2020-9309 x_refsource_CONFIRM