#VU82071 Improper Restriction of Excessive Authentication Attempts in Nextcloud Enterprise Server and Nextcloud Server - CVE-2023-45148

Vulnerability identifier: #VU82071

Vulnerability risk: Low

CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-45148

CWE-ID: CWE-307

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Nextcloud Enterprise Server
Client/Desktop applications / Messaging software
Nextcloud Server
Client/Desktop applications / Messaging software

Vendor: Nextcloud

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to improper rate limiter when Memcached is installed. A remote user can cause the rate limiting in Nextcloud Server could be reset unexpectedly resetting the rate count earlier than intended.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Nextcloud Enterprise Server: 22.0.0 - 27.0.2

Nextcloud Server: 25.0.0 - 27.0.2

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External links
https://github.com/nextcloud/server/pull/40293
https://hackerone.com/reports/2110945
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-xmhp-7vr4-hp63

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.