CVE-2021-30479

mediumpriority · track · 21EPSS 0.009 · 58 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.86% (58th) EPSS

CVSS 5 · medium

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

5.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-269USprimary

affected products (2)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
zulip zulip server< 3.4nvdUScpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-04-15modified 2026-06-17

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references (5)

External citations — patches, advisories, analysis.

scry

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