PT-2021-22472 · Nextcloud · Nextcloud Contacts

Lukas Reschke · Published 2021-10-25 · Updated 2021-10-27 · CVE-2021-39221

Positive Technologies (AI Summary)

CVSS v3.1

6.4

Medium

Base vector

AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N

Name of the Vulnerable Software and Affected Versions Nextcloud Contacts versions prior to 4.0.3

Description The Nextcloud Contacts application is vulnerable to a stored Cross-Site Scripting (XSS) issue. To exploit this, a user must right-click on a malicious file and open it in a new tab. However, due to the strict Content-Security-Policy in Nextcloud, this issue is not exploitable on modern browsers that support Content-Security-Policy.

Recommendations For versions prior to 4.0.3, upgrade the Nextcloud Contacts application to version 4.0.3. As a temporary workaround, consider using a browser that supports Content-Security-Policy to minimize the risk of exploitation.

Fix

Unrestricted File Upload

XSS

Weakness Enumeration

CWE-434

CWE-79

Related Identifiers

CVE-2021-39221

GHSA-J6CX-MXQF-F9VC

Affected Products

Nextcloud Contacts

References · 7

• https://osv.dev/vulnerability/CVE-2021-39221 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-39221 · Security Note
• https://github.com/nextcloud/contacts/pull/2407 · Note
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-j6cx-mxqf-f9vc · Note
• https://t.me/cvenotify/22481 · Telegram Post
• https://t.me/cvenotify/22364 · Telegram Post
• https://t.me/cibsecurity/31172 · Telegram Post