An issue was discovered in Zammad before 3.4.1.
Priority LOW 30CWE-863Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-863.
Summary
An issue was discovered in Zammad before 3.4.1. There are wrong authorization checks for impersonation requests via X-On-Behalf-Of. The authorization checks are performed for the actual user and not the one given in the X-On-Behalf-Of header.
Why it matters now
EPSS 0.00787 56th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:zammad:zammad:*:*:*:*:*:*:*:* | 1.0.0 to before 3.4.1 | Vulnerable | Zammad GmbH |
- cpe:2.3:a:zammad:zammad:*:*:*:*:*:*:*:* Versions 1.0.0 to before 3.4.1 Vulnerable ·Zammad GmbH
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-26029
- 2026-10-03 Alias added: GHSA-rvr3-f3x4-3669
References
More Zammad GmbH Zammad vulnerabilities
- TI-2026-65406 Local privilege escalation in Zammad v1.5.0 to v7.2.2 installed via DEB or RPM package KEVCVSS 4.0CRITICAL 9.4
- TI-2026-65405 Undisclosed RCE in Zammad v6.3 and higher KEVCVSS 4.0CRITICAL 9.4
- TI-2024-22252 An issue was discovered in Zammad before 6.3.0. CVSS 3.1CRITICAL 9.1
- TI-2022-23785 A vulnerability in Zammad v5.3.0 allows attackers to execute arbitrary code or escalate… CVSS 3.1CRITICAL 9.8
- TI-2021-18599 An issue was discovered in Zammad before 4.1.1. CVSS 3.1CRITICAL 9.8
- TI-2021-18603 An issue was discovered in Zammad before 4.1.1. CVSS 3.1CRITICAL 9.8
Sources
- CVE-2020-26029 · CVE Program
- CVE-2020-26029 · NVD
- FIRST EPSS
- GHSA-rvr3-f3x4-3669 · GitHub Advisory Database · CC BY 4.0
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