What is CVE-2025-66592?

CVE-2025-66592 is a medium-severity vulnerability in Synology Active_backup_for_business_agent, classified under Origin Validation Error. CVSS score: 6.1/10. Published 2026-05-27.

How severe is CVE-2025-66592?

Medium severity. CVSS v3 base score is 6.1 out of 10.

Vulnerability in Synology Active_backup_for_business_agent

CVE-2025-66592

An origin validation error vulnerability in Synology Active Backup for Business Agent before 3.1.0-4967 allows local users to write arbitrary files with restricted content and conduct denial-of-service during installation.

EPSS: 0.000 (0.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H.

Affected products

Synology Active_backup_for_business_agent
Synology Active Backup For Business Agent

Weakness classification (CWE)

CWE-346 — Origin Validation Error

References

security@synology.com (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2025-66592?: CVE-2025-66592 is a medium-severity vulnerability in Synology Active_backup_for_business_agent, classified under Origin Validation Error. CVSS score: 6.1/10. Published 2026-05-27.
How severe is CVE-2025-66592?: Medium severity. CVSS v3 base score is 6.1 out of 10.