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Vulnerability record · CVE-2021-3967 · published 26 February 2022
CVE-2021-3967: Zulip improper access control vulnerability
Zulip · Zulip
Improper Access Control in GitHub repository zulip/zulip prior to 4.10.
8.8 CVSS 3.1 High EPSS 0.84% · top 43.9% CWE-284 · Improper access control
8.8CVSS 3.1 base score, v2 6.5
0.84%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References, 2 tagged exploit
17 Jun 2026Last modified by NVD
Description
Improper Access Control in GitHub repository zulip/zulip prior to 4.10.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://github.com/zulip/zulip/commit/d5db254ca8167995a1654d1c45ffc74b2fade39a | PatchThird Party Advisory |
| https://huntr.dev/bounties/2928a625-0467-4a0a-b4e2-e27322786686 | ExploitThird Party Advisory |
| https://github.com/zulip/zulip/commit/d5db254ca8167995a1654d1c45ffc74b2fade39a | PatchThird Party Advisory |
| https://huntr.dev/bounties/2928a625-0467-4a0a-b4e2-e27322786686 | ExploitThird Party Advisory |
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
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Source: NIST National Vulnerability Database (record CVE-2021-3967), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.
