CVE-2024-56136: zulip server Information Disclosure

Description

Zulip server provides an open-source team chat that helps teams stay productive and focused. Zulip Server 7.0 and above are vulnerable to an information disclose attack, where, if a Zulip server is hosting multiple organizations, an unauthenticated user can make a request and determine if an email address is in use by a user. Zulip Server 9.4 resolves the issue, as does the `main` branch of Zulip Server. Users are advised to upgrade. There are no known workarounds for this issue.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Weakness Type (CWE)

CWE-200 CWE-200

Affected Products

Vendor	Product	Versions
zulip	zulip_server	7.0 — 9.4

References

Advisories & Patches

https://github.com/zulip/zulip/commit/c6334a765b1e6d71760e4a3b32ae5b8367f2ed4d

Other References

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

Frequently Asked Questions

What is CVE-2024-56136? +

Zulip server provides an open-source team chat that helps teams stay productive and focused. Zulip Server 7.0 and above are vulnerable to an information disclose attack, where, if a Zulip server is hosting multiple organizations, an unauthenticated user can make a request and determine if an email address is in use by a user. Zulip Server 9.4 resolves the issue, as does the `main` branch of Zulip Server. Users are advised to upgrade. There are no known workarounds for this issue. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2024-56136? +

CVE-2024-56136 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-56136? +

CVE-2024-56136 affects products from zulip, specifically: zulip_server. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-56136? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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