ReviewHigh

CVE-2026-23933

Zabbix

In Zabbix 7.4 the cryptographic key used for signing Frontend sessions has been erroneously written to the database seed. Currently the only known exploitation scenario is for deployments that utilize both - SAML authentication and guest users. In such cases the key can be used to forge valid session cookies, potentially leading to unauthorized access. For other Zabbix deployments this does not have a known impact.

CVSS: 7.7
EPSS: 0.20%
CISA KEV: Not listed
Published: 2026.08.18

PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.20%

Technical severityCVSS 7.7

Vulnerability overview

Affected product and versions

Product: Zabbix
Affected versions: >= 7.4.0 <= 7.4.10
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Zabbix and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE: CWE-259