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TI-2025-20006 Aliases CVE-2025-27149

Zulip exports can leak private data

Priority LOW 21CWE-497Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
Active
Attack complexity
Low
Attack requirements
None
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-497.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00305 23rd percentileScored 2026-11-07
Fix Fixed zulip (zulip): 10.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
zulipzulip2.1.0 to before 10.010.0Patch availableCNA
  • zulip Vendorzulip Affected 2.1.0 to before 10.0 Fixed in 10.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:*2.1.0 to before 10.0Vulnerablezulip
  • cpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:* Versions 2.1.0 to before 10.0 Vulnerable ·zulip

Remediation

  • Fix · CNA zulip (zulip) Fixed in 10.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-27149

References

Advisory 1

  • TI-2024-37129 /api/v1/jwt/fetch_api_key endpoint can leak if an email address has an account in Zulip server CVSS 4.0MEDIUM 6.9
  • TI-2022-06082 Multi-use invitations can grant access to other organizations in Zulip CVSS 3.1CRITICAL 9.8
  • TI-2019-13649 In Zulip Server versions from 1.7.0 to before 2.0.7, a bug in the new user signup process… CVSS 3.1CRITICAL 9.8
  • TI-2025-22659 Zulip Authentication Backend Configuration Bypass CVSS 3.1HIGH 8.2
  • TI-2024-24345 Zulip from 8.0 to 8.3 contains a memory leak vulnerability in the handling of popovers. CVSS 3.1HIGH 7.5
  • TI-2020-11848 Zulip Server 2.x before 2.1.7 allows eval injection if a privileged attacker were able to… CVSS 3.1HIGH 8.8
See all 39 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences