CVE-2020-9309
8.8 · HIGHOverview
CVE-2020-9309 is a high-severity vulnerability affecting silverstripe mimevalidator. It was published on July 15, 2020 and has a CVSS 3.1 base score of 8.8 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from silverstripe. Update mimevalidator to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| silverstripe | mimevalidator | >= 0, < 2.0.0 | Affected |
| silverstripe | recipe | >= 4.0.0, < 4.6.0 | Affected |
Frequently Asked Questions
What is CVE-2020-9309?
CVE-2020-9309 is a high-severity vulnerability affecting silverstripe mimevalidator. It was published on July 15, 2020 and has a CVSS 3.1 base score of 8.8 (HIGH).
How severe is CVE-2020-9309?
This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2020-9309?
Check the references section for vendor advisories and patches from silverstripe. Update mimevalidator to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2020-9309?
CyberStrike's AI-powered security agents can automatically detect CVE-2020-9309 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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