Medium severity · published Dec 28, 2020
CVE-2020-26029
An issue was discovered in Zammad before 3.4.1
6.5
CVSS
0.8%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZA
Zammad · Zammad
1.0.0 before 3.4.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-26029
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-26029
Vendor Advisory
https://zammad.com/news/security-advisory-zaa-2020-20
More from Zammad
9.8
CVE-2026-102489
Undisclosed RCE in Zammad v6.3 and higher
7.8
CVE-2026-102490
Local privilege escalation in Zammad v1.5.0 to v7.2.2 installed via DEB or RPM package
9.8
CVE-2022-48021
A vulnerability in Zammad v5.3.0 allows attackers to execute arbitrary code or escalate privileges via a crafted message sent to the server
9.8
CVE-2022-35490
Zammad 5.2.0 is vulnerable to privilege escalation
9.8
CVE-2021-42090
An issue was discovered in Zammad before 4.1.1
