CVE-2021-39221: 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…

PriorityP424medium5.4CVSS 3.1

AVNACLPRLUIRSCCLILAN

EPSS

0.50%

39.4th percentile

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

2 ranges

Vendor	Product	Version range	Fixed in
nextcloud	contacts	< 4.0.3	4.0.3
nextcloud	security-advisories	< 4.0.3	4.0.3

CVSS provenance

nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

nvdv2.03.5LOWAV:N/AC:M/Au:S/C:N/I:P/A:N

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