#VU74599 Information disclosure in Nextcloud Server and Nextcloud Enterprise Server - CVE-2023-28834

Vulnerability identifier: #VU74599

Vulnerability risk: Low

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

CVE-ID: CVE-2023-28834

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: No

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

Vendor: Nextcloud

Description

The vulnerability allows a remote user to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application. A remote user can obtain the full data directory path of the Nextcloud server from an API endpoint.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Nextcloud Server: 23.0.0 - 25.0.5

Nextcloud Enterprise Server: 23.0.0 - 25.0.3

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External links
https://github.com/nextcloud/server/issues/33883
https://hackerone.com/reports/1690510
https://github.com/nextcloud/server/pull/36094
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-5w64-6c42-rgcv

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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.