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TI-2024-37129 Aliases CVE-2024-56136

/api/v1/jwt/fetch_api_key endpoint can leak if an email address has an account in Zulip server

Priority HIGH 70CWE-200Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
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-200.

Summary

Zulip server provides an open-source team chat that helps teams stay productive and focused. Zulip Server 7.0 and above are vulnerable to an information disclose attack, where, if a Zulip server is hosting multiple organizations, an unauthenticated user can make a request and determine if an email address is in use by a user. Zulip Server 9.4 resolves the issue, as does the `main` branch of Zulip Server. Users are advised to upgrade. There are no known workarounds for this issue.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00587 48th percentileScored 2026-11-07
Fix Fixed zulip (zulip): 9.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
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
zulipzulip7.0 to before 9.49.4Patch availableCNA
  • zulip Vendorzulip Affected 7.0 to before 9.4 Fixed in 9.4 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:*7.0 to before 9.4Vulnerablezulip
  • cpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:* Versions 7.0 to before 9.4 Vulnerable ·zulip

Remediation

  • Fix · CNA zulip (zulip) Fixed in 9.4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-56136

References

Patch 1

Advisory 1

  • 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
  • TI-2017-00857 Incorrect authorization in Zulip Server CVSS 3.0HIGH 8.8
See all 39 →

Sources

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