#VU102877 Information disclosure in Zulip Server - CVE-2024-56136

Vulnerability identifier: #VU102877

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2024-56136

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 attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application in the /api/v1/jwt/fetch_api_key endpoint. A remote attacker can make a request and determine if an email address is in use by a user.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Zulip Server: 7.0 beta1 - 9.3

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External links
https://github.com/zulip/zulip/security/advisories/GHSA-5xg8-xhfj-4hm6

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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