Medium severity · published Oct 5, 2026
CVE-2026-59786
Active agent heartbeat missing TLS check
6.9
CVSS
0.2%
EPSS
No
On KEV
Description
Zabbix Server and Proxy accept the active agent heartbeat message regardless of the configured PSK or certificate authentication. This means someone with access to the Zabbix trapper port can report an arbitrary host using an active agent as available, resulting in a loss of integrity.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZA
Zabbix · Zabbix
7.0.0 through 7.0.28; 7.4.0 through 7.4.12 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59786
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-59786
support.zabbix.com
https://support.zabbix.com/browse/ZBX-28196
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