CVE-2025-27149
lowpriority · track · 11EPSS 0.003 · 23 %ileEUUSEPSS · scored 2026-10-27
Zulip server provides an open-source team chat that helps teams stay productive and focused. Prior to 10.0, the data export to organization administrators feature in Zulip leaks private data. The collection of user-agent types identifying specific integrations or HTTP libraries (E.g., ZulipGitlabWebhook, okhttp, or PycURL) that have been used to access any organization on the server was incorrectly included in all three export types, regardless of if they were used to access the exported organization or not. The "public data" and "with consent" exports metadata including the titles of some topics in private channels which the administrator otherwise did not have access to, and none of the users consented to exporting and metadata for which users were in a group DM together. This vulnerability is fixed in 10.0.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1–4.6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (2)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
- https://github.com/zulip/zulip/security/advisories/GHSA-358p-x39m-99mmcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2025-27149cnnvd
- https://github.com/zulip/zulip/security/advisories/GHSA-358p-x39m-99mmenisa_euvd
- https://github.com/zulip/zulip/security/advisories/GHSA-358p-x39m-99mmThird Party Advisorynvd
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