Medium severity · published Apr 14, 2021
CVE-2021-30479
An issue was discovered in Zulip Server before 3.4
5.3
CVSS
0.9%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZS
Zulip Server · Zulip
before 3.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-30479
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-30479
Vendor Advisory
https://blog.zulip.com/2021/04/14/zulip-server-3-4/
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