CVE-2021-43856 Explained : Impact and Mitigation
Learn about CVE-2021-43856 impacting Wiki.js versions prior to 2.5.264. Discover the stored cross-site scripting vulnerability and the necessary steps for mitigation and prevention.
Wiki.js 2.5.263 and earlier versions are prone to stored cross-site scripting through non-image file uploads, allowing attackers to execute malicious JavaScript. The vulnerability has been patched in version 2.5.264.
Understanding CVE-2021-43856
What is CVE-2021-43856?
Wiki.js, a Node.js-based wiki application, is susceptible to stored cross-site scripting via certain file uploads, potentially enabling attackers to execute harmful scripts.
The Impact of CVE-2021-43856
The vulnerability poses a high severity risk with a CVSS base score of 8.2, affecting confidentiality and potentially allowing for malicious JavaScript execution.
Technical Details of CVE-2021-43856
Vulnerability Description
The flaw in Wiki.js allows for stored cross-site scripting via non-image file uploads, potentially compromising user data and system integrity.
Affected Systems and Versions
- Product: Wiki
- Vendor: Requarks
- Vulnerable Versions: < 2.5.264
Exploitation Mechanism
Attackers can abuse the vulnerability by crafting malicious files that execute JavaScript when accessed directly via the browser.
Mitigation and Prevention
Immediate Steps to Take
- Apply the patch provided in version 2.5.264 to mitigate the vulnerability.
- Consider disabling file uploads for untrusted users as a temporary workaround.
Long-Term Security Practices
- Regularly update Wiki.js to the latest version to avoid known vulnerabilities.
- Implement secure file upload policies and user permissions within the application.
Patching and Updates
Ensure timely updates and patches are applied to address any security vulnerabilities.