Auth bypass in Zulip
CVE-2026-115574
Zulip is an open-source team collaboration tool. From 11.0 until 12.2, organizations with web-public channels enabled exposed the GET /json/users endpoint to logged-out spectators, and a missing access-control check allowed include_custom_profile_fields=true to return every user's custom profile field values in addition to the documented limited directory data. This exposed those custom profile field values to unauthenticated visitors. This issue is fixed in version 12.2.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Zulip — versions >= 11.0, < 12.2
Weakness classification (CWE)
References
- https://github.com/zulip/zulip/commit/6f33a8fa345ba776039a3f46131c253599a3ba15
- https://github.com/zulip/zulip/commit/774d4c7b12755178fa406f0c0f3b2cafdbbec32c
- https://github.com/zulip/zulip/pull/39913
- https://github.com/zulip/zulip/releases/tag/12.2
- https://github.com/zulip/zulip/security/advisories/GHSA-3m37-hwq6-jrj8
- https://zulip.readthedocs.io/en/latest/overview/changelog.html#zulip-server-12-2
Frequently asked questions
- What is CVE-2026-115574?
- CVE-2026-115574 is a medium-severity vulnerability in Zulip, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-11-04.
- How severe is CVE-2026-115574?
- Medium severity. CVSS v3 base score is 5.3 out of 10.