XSS in Zulip
CVE-2026-24050
Zulip is an open-source team collaboration tool. From 5.0 to before 11.5, some administrative actions on the user profile were susceptible to stored XSS in group names or channel names. Exploiting these vulnerabilities required the user explicitly interacting with the problematic object. This vulnerability is fixed in 11.5.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (17.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 17.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.000
Affected products
- Zulip — versions >= 5.0, < 11.5
- Zulip Server
Weakness classification (CWE)
References
- github.com/zulip/zulip/security/advisories/GHSA-56qv-8823-6fq9 (Vendor Advisory)
- github.com/zulip/zulip/commit/e6093d9e4788f4d82236d856c5ed7b16767886a7 (Patch)
- github.com/zulip/zulip/releases/tag/11.5 (Release Notes)
- zulip.readthedocs.io/en/latest/overview/changelog.html (Release Notes)
Frequently asked questions
- What is CVE-2026-24050?
- CVE-2026-24050 is a medium-severity vulnerability in Zulip, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-02-06.
- How severe is CVE-2026-24050?
- Medium severity. CVSS v3 base score is 5.4 out of 10.