#VU77659 Open redirect in Nextcloud Server and Nextcloud Enterprise Server - CVE-2023-35171

Vulnerability identifier: #VU77659

Vulnerability risk: Low

CVSSv4.0: 0.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-35171

CWE-ID: CWE-601

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 attacker to redirect victims to arbitrary URL.

The vulnerability exists due to improper sanitization of user-supplied data on "Unsupported browser" warning. A remote user can create a link that leads to a trusted website, however, when clicked, redirects the victim to arbitrary domain.

Successful exploitation of this vulnerability may allow a remote attacker to perform a phishing attack and steal potentially sensitive information.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Nextcloud Server: 26.0.0 - 26.0.1

Nextcloud Enterprise Server: 26.0.0 - 26.0.1

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External links
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-h353-vvwv-j2r4

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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.