CVE-2021-41177 Information

Description

Nextcloud is an open-source self-hosted productivity platform. Prior to versions 20.0.13 21.0.5 and 22.2.0 Nextcloud Server did not implement a database backend for rate-limiting purposes. Any component of Nextcloud using rate-limits (as as AnonRateThrottle or UserRateThrottle) was thus not rate limited on instances not having a memory cache backend configured. In the case of a default installation this would notably include the rate-limits on the two factor codes. It is recommended that the Nextcloud Server be upgraded to 20.0.13 21.0.5 or 22.2.0. As a workaround enable a memory cache backend in config.php.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Reference

https://github.com/nextcloud/security-advisories/security/advisories/GHSA-fj39-4qx4-m3f2 https://hackerone.com/reports/1265709 https://github.com/nextcloud/server/pull/28728

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

NONE

Base Score

HIGH

Base Severity

8.1