CVE-2021-39221

XSS in Contacts

Description

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.

Category

6.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: nextcloud security-advisories
Published at:
Updated at:

References

Link Tags
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j6cx-mxqf-f9vc third party advisory
https://github.com/nextcloud/contacts/pull/2407 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-39221?
CVE-2021-39221 has been scored as a medium severity vulnerability.
How to fix CVE-2021-39221?
To fix CVE-2021-39221, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-39221 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-39221 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-39221?
CVE-2021-39221 affects nextcloud security-advisories.
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