Hardcoded session key in Zabbix 7.4
Summary
| CVE | CVE-2026-23933 |
|---|---|
| State | PUBLISHED |
| Assigner | Zabbix |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-18 13:17:21 UTC |
| Updated | 2026-08-19 04:16:58 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v4.0 7.7 HIGH from [email protected]
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
EPSS: 0.001990000 probability, percentile 0.100680000 (date 2026-08-19)
Problem Types: CWE-259 | CWE-259 CWE-259 CWE-259: Use of Hard-coded Password
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 7.7 | HIGH | 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/C... |
| 4.0 | CNA | CVSS | 7.7 | HIGH | 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 |
CVSS v4.0 Breakdown
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
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| support.zabbix.com/browse/ZBX-28071 | [email protected] | support.zabbix.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Zabbix wants to thank Daniel Shemesh and Or Ida for submitting this report on the HackerOne bug bounty platform. (en)
Additional Advisory Data
Solutions
CNA: Upgrade Zabbix Server to the latest version, an upgrade patch will remove the session key from the DB.
Workarounds
CNA: As a workaround, the pre-seeded session key can be manually cleared from Zabbix DB by setting value of 'settings.session_key' to an empty string. Zabbix Frontend will then generate a new random key.