CVE-2021-39221: XSS in Contacts
Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud Contacts application prior to version 4.0.3 was vulnerable to a stored Cross-Site Scripting (XSS) vulnerability. For exploitation, a user would need to right-click on a malicious file and open the file in a new tab. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. It is recommended that the Nextcloud Contacts application is upgraded to 4.0.3. As a workaround, one may use a browser that has support for Content-Security-Policy.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2021-39221?
CVE-2021-39221 is a stored Cross-Site Scripting (XSS) vulnerability in the Nextcloud Contacts application prior to version 4.0.3.
How does the vulnerability in Nextcloud Contacts work?
The vulnerability requires a user to right-click on a malicious file and open it in a new tab, allowing the execution of malicious scripts.
What is the severity of CVE-2021-39221?
CVE-2021-39221 has a severity rating of medium with a CVSS score of 5.4.
Is there a fix for CVE-2021-39221?
Yes, the vulnerability has been fixed in Nextcloud Contacts version 4.0.3.
Where can I find more information about CVE-2021-39221?
You can find more information about CVE-2021-39221 in the Nextcloud Contacts GitHub repository and Nextcloud's security advisories.