Improper validation of custom installation directories on Windows could allow installation into locations with unsafe permissions, increasing the risk of DLL sideloading.
Summary
| CVE | CVE-2026-59781 |
|---|---|
| State | PUBLISHED |
| Assigner | Zabbix |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-18 13:17:25 UTC |
| Updated | 2026-08-19 04:17:27 UTC |
| Description | When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios. |
Risk And Classification
Primary CVSS: v4.0 5.4 MEDIUM from [email protected]
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/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: 0.001120000 probability, percentile 0.016180000 (date 2026-08-19)
Problem Types: CWE-427 | CWE-427 CWE-427: Uncontrolled Search Path Element
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 5.4 | MEDIUM | CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 5.4 | MEDIUM | CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
CVSS v4.0 Breakdown
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/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-28077 | [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 Kazuma Matsumoto of GMO Cybersecurity by IERAE, Inc. for finding and reporting this issue. (en)
Additional Advisory Data
Solutions
CNA: Update the affected components to their respective fixed versions.
Workarounds
CNA: Install the Zabbix Agent into directories with appropriately restricted access permissions. Verify and adjust permissions on custom installation directories to prevent unprivileged users from modifying their contents.