#VU106254 Information disclosure in Zulip Server - CVE-2025-27149

Vulnerability identifier: #VU106254

Vulnerability risk: Low

CVSSv4.0: 1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-27149

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Zulip Server
Web applications / Other software

Vendor: Zulip

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 within non-exported messages and client user agent strings. A remote administrator can gain unauthorized access to sensitive information on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Zulip Server: 2.1.0 - 9.4

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External links
https://github.com/zulip/zulip/security/advisories/GHSA-358p-x39m-99mm

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Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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