CVE-2021-41178

File Traversal affecting SVG files on Nextcloud Server

State: Published
Severity: 8.8 High
Published: Oct 25, 2021
Updated: Aug 4, 2024
Reserved: Sep 15, 2021

Description

Nextcloud is an open-source, self-hosted productivity platform. Prior to versions 20.0.13, 21.0.5, and 22.2.0, a file traversal vulnerability makes an attacker able to download arbitrary SVG images from the host system, including user provided files. This could also be leveraged into a XSS/phishing attack, an attacker could upload a malicious SVG file that mimics the Nextcloud login form and send a specially crafted link to victims. The XSS risk here is mitigated due to the fact that Nextcloud employs a strict Content-Security-Policy disallowing execution of arbitrary JavaScript. It is recommended that the Nextcloud Server be upgraded to 20.0.13, 21.0.5 or 22.2.0. There are no known workarounds aside from upgrading.

Scores

CVSS	Score	Vector	Source
3.1	8.8 High	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	GitHub_M

Weaknesses

CWE-23 Relative Path Traversal
CWE-434 Unrestricted Upload of File with Dangerous Type

Affected Products

Product	Versions
security-advisoriesnextcloud	20.0.13Affected >= 21.0.0, < 21.0.5Affected < 22.2.0Affected

References

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