CVE Vulnerabilities

CVE-2023-28847

Improper Restriction of Excessive Authentication Attempts

Published: Apr 25, 2023 | Modified: May 04, 2023
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. In Nextcloud Server 24.0.0 prior to 24.0.11 and 25.0.0 prior to 25.0.5; as well as Nextcloud Server Enterprise 23.0.0 prior to 23.0.12.6, 24.0.0 prior to 24.0.11, and 25.0.0 prior to 25.0.5; an attacker is not restricted in verifying passwords of share links so they can just start brute forcing the password. Nextcloud Server 24.0.11 and 25.0.5 and Nextcloud Enterprise Server 23.0.12.6, 24.0.11, and 25.0.5 contain a fix for this issue. No known workarounds are available.

Weakness

The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame, making it more susceptible to brute force attacks.

Affected Software

Name Vendor Start Version End Version
Nextcloud_server Nextcloud 23.0.0 (including) 23.0.12.6 (excluding)
Nextcloud_server Nextcloud 24.0.0 (including) 24.0.11 (excluding)
Nextcloud_server Nextcloud 25.0.0 (including) 25.0.5 (excluding)

Potential Mitigations

  • Common protection mechanisms include:

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • Consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator. [REF-45]

References