Medium severity · published Aug 18, 2026
CVE-2026-23934
Frontend DoS via the validate.api.exists action
6.5
CVSS
0.6%
EPSS
No
On KEV
Description
An authenticated user is able to cause disproportionate CPU load on the Frontend webserver by sending specifically crafted requests to the Frontend validate.api.exists action, leading to potential denial of service.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 46% 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 7.4.11 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-23934
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-23934
Vendor Advisory
https://support.zabbix.com/browse/ZBX-28072
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