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CVE-2021-3967Improper Access Control in zulip/zulip
- 4.1MediumCVSS base score
- 0.84%Exploitation in 30 daysEPSS · top 42% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Improper Access Control in GitHub repository zulip/zulip prior to 4.10.
Timeline
ID reserved
By @huntrdev
- 3 months later
· 3 months later
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| @huntrdevCNA (assigner) | 3.0 | Medium4.1 | CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L |
| NVDNVD · Modified | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.84% · top 42% of all CVEs (13 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.1.
Affected products
- affected unspecified – < 4.10
References
References2
- https://huntr.dev/bounties/2928a625-0467-4a0a-b4e2-e27322786686 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/zulip/zulip/commit/d5db254ca8167995a1654d1c45ffc74b2fade39a (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-27172 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-3967)Record last updated .