Detections
Analytics

Zabbix Server 7.4.x < 7.4.11 Authentication Bypass (ZBX-28071)

high Nessus Plugin ID 338766

Synopsis

A monitoring application installed on the remote host is affected by an authentication bypass vulnerability.

Description

The version of Zabbix Server installed on the remote host is 7.4.x prior to 7.4.11. It is, therefore, affected by an authentication bypass vulnerability:

 - The cryptographic key used for signing Frontend sessions has been erroneously written to the database seed. In deployments that utilize both SAML authentication and guest users, the key can be used to forge valid session cookies, potentially leading to unauthorized access. (CVE-2026-23933)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to Zabbix version 7.4.11 or later.

See Also

https://support.zabbix.com/browse/ZBX-28071

Plugin Details

Severity: High

ID: 338766

File Name: zabbix_ZBX-28071.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 8/21/2026

Updated: 8/21/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.53

CVSS v2

Risk Factor: Medium

Base Score: 5.8

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:N

CVSS Score Source: CVE-2026-23933

CVSS v3

Risk Factor: High

Base Score: 7.4

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS v4

Risk Factor: High

Base Score: 7.7

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

Vulnerability Information

CPE: cpe:/a:zabbix:zabbix_server

Required KB Items: installed_sw/Zabbix Server

Patch Publication Date: 8/18/2026

Vulnerability Publication Date: 8/18/2026

Reference Information

CVE: CVE-2026-23933

CWE: 259