CVE-2026-59781 PUBLISHED

Improper validation of custom installation directories on Windows could allow installation into locations with unsafe permissions, increasing the risk of DLL sideloading.

Assigner: Zabbix
Reserved: 07.07.2026 Published: 18.08.2026 Updated: 19.08.2026

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.

Metrics

CVSS Vector: 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 Score: 5.4

Product Status

Vendor Zabbix
Product Zabbix
Versions Default: unknown
  • affected from 7.4.0 to 7.4.12 (incl.)
  • affected from 7.0.0 to 7.0.28 (incl.)
  • affected from 6.0.0 to 6.0.47 (incl.)

Affected Configurations

An attacker with the ability to write files to an insecure custom installation directory could place a malicious DLL that may be loaded by the application due to the Windows DLL search order.

Workarounds

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.

Solutions

Update the affected components to their respective fixed versions.

Credits

  • Zabbix wants to thank Kazuma Matsumoto of GMO Cybersecurity by IERAE, Inc. for finding and reporting this issue. reporter

References

Problem Types

  • CWE-427: Uncontrolled Search Path Element CWE

Impacts

  • CAPEC-471: DLL Search Order Hijacking