CVE-2020-26030 json
An issue was discovered in Zammad before 3.4.1.
published 2020-12-28 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-18660
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.4%
- EPSS 1.4% chance of exploitation in 30 days, percentile 71%
- public exploits
- 0
- none known
Summary
An issue was discovered in Zammad before 3.4.1. There is an authentication bypass in the SSO endpoint via a crafted header, when SSO is not configured. An attacker can create a valid and authenticated session that can be used to perform any actions in the name of other users.
Patch / fix
- zammad zammad 3.4.1
Exploit prediction
1.35% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-287 Improper Authentication
References
-
zammad.com
/news/security-advisory-zaa-2020-18
vendor-advisory
Sources
- CVE List CVE-2020-26030
- NVD CVE-2020-26030
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