CVE-2021-30478 json
An issue was discovered in Zulip Server before 3.4.
published 2021-04-14 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-17401
- cvss
- 4.3
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 47%
- public exploits
- 0
- none known
Summary
An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the can_forge_sender permission (previously is_api_super_user) resulted in users with this permission being able to send messages appearing as if sent by a system bot, including to other organizations hosted by the same Zulip installation.
Patch / fix
- zulip zulip_server 3.4
Exploit prediction
0.57% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N |
| NVD | 2.0 | 4.0 | AV:N/AC:L/Au:S/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-269 Improper Privilege Management
References
-
blog.zulip.com
/2021/04/14/zulip-server-3-4/
release-notes, vendor-advisory
Sources
- CVE List CVE-2021-30478
- NVD CVE-2021-30478
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.