CVE-2021-39222

Summary

Nextcloud is an open-source, self-hosted productivity platform. The Nextcloud Talk application 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 Talk application is upgraded to patched versions 10.0.7, 10.1.4, 11.1.2, 11.2.0 or 12.0.0. As a workaround, use a browser that has support for Content-Security-Policy.

Affected Software

VendorProductVersion RangeStatus
nextcloudsecurity-advisories< 10.0.7affected
nextcloudsecurity-advisories>= 10.1.0, < 10.1.4affected
nextcloudsecurity-advisories>= 11.1.0, < 11.1.2affected
nextcloudsecurity-advisories< 11.2.0affected
nextcloudsecurity-advisories>= 12.0.0.alpha-1, < 12.0.0affected

Weaknesses

  • CWE-434: CWE-434: Unrestricted Upload of File with Dangerous Type
  • CWE-79: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

ADP Enrichment

CVE Program Container

Additional References

References