{"cve":"CVE-2026-100404","nvd":{"published":"2026-10-14T16:17:28.860","modified":"2026-10-16T16:00:33.533","status":"Awaiting Analysis","description":"Zulip is an open-source team collaboration tool. In Zulip Server versions through 12.1, guest users can receive new message events for public channels outside their subscriptions. A guest can trigger the issue by registering an event queue with parameters that request messages from an unsubscribed public channel, or an existing event queue can remain affected after the guest's access to the channel is removed. The flaw discloses new public-channel messages to the guest. This issue is fixed in version 12.2.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","score":6.5},"cwes":["CWE-862"],"references":["https://github.com/zulip/zulip/commit/98659a41cb93d4ce329ea14bb0cdfb4b147500ba","https://github.com/zulip/zulip/commit/c03db8916456674df3c98614f6f0ef8cd024ef11","https://github.com/zulip/zulip/pull/39913","https://github.com/zulip/zulip/releases/tag/12.2","https://github.com/zulip/zulip/security/advisories/GHSA-5r8f-gq2h-fcgp"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:59:28.494260111+00:00"},"epss":{"cve":"CVE-2026-100404","score":0.00415,"percentile":0.35515,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}