High severity · published Mar 3, 2021
CVE-2021-27927
In Zabbix from 4.0.x before 4.0.28rc1, 5.0.0alpha1 before 5.0.10rc1, 5.2.x before 5.2.6rc1, and 5.4.0alpha1 before 5.4.0beta2, the CControllerAuthenticationUpdate controller lacks…
8.8
CVSS
2.2%
EPSS
No
On KEV
Description
In Zabbix from 4.0.x before 4.0.28rc1, 5.0.0alpha1 before 5.0.10rc1, 5.2.x before 5.2.6rc1, and 5.4.0alpha1 before 5.4.0beta2, the CControllerAuthenticationUpdate controller lacks a CSRF protection mechanism. The code inside this controller calls diableSIDValidation inside the init() method. An attacker doesn't have to know Zabbix user login credentials, but has to know the correct Zabbix URL and contact information of an existing user with sufficient privileges.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.2% · higher than 82% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZA
Zabbix · Zabbix
4.0.0 through 4.0.27; 5.0.0 through 5.0.9; 5.2.0 through 5.2.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27927
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27927
lists.debian.org
https://lists.debian.org/debian-lts-announce/2023/04/msg00013.html
Issue Tracking
https://support.zabbix.com/browse/ZBX-18942
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