Medium severity · published Mar 24, 2026
CVE-2026-23923
Unauthenticated arbitrary PHP class instantiation
5.3
CVSS
0.3%
EPSS
No
On KEV
Description
An unauthenticated attacker can exploit the Frontend 'validate' action to blindly instantiate arbitrary PHP classes. The impact depends on environment setup but appears limited at this time.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZA
Zabbix · Zabbix
7.4.0 through 7.4.6 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-23923
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-23923
Vendor Advisory
https://support.zabbix.com/browse/ZBX-27641
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