Home/CVE/An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the all_public_streams API feature re
CVE

CVE-2021-30479

An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the all_public_streams API feature re

An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the all_public_streams API feature resulted in guest users being able to receive message traffic to public streams that should have been only accessible to members of the organization.

MEDIUM · CVSS 5.3 EPSS 0.00203
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-269Improper Privilege Management
▤

Affected Products & Versions

1
zulip server< 3.4
▣

Scoring & Timeline

5.3
MEDIUM · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD15 Apr 2021 · 12:15 AM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://blog.zulip.com/2021/04/14/zulip-server-3-4/Vendor Advisory
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