---
id: CVE-2025-66592
title: >-
  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.
summary: >-
  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.
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H'
cwe:
  - CWE-346
vendor: synology
product: active_backup_for_business_agent
affected:
  - active_backup_for_business_agent < 3.1.0-4967
patched:
  - active_backup_for_business_agent 3.1.0-4967
published: '2026-05-27'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T21:10:00.190'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-66592'
references:
  - url: 'https://www.synology.com/en-global/security/advisory/Synology_SA_25_16'
    label: security@synology.com
tags:
  - nvd
epss: 0.00086
epssPercentile: 0.003
ingestedAt: '2026-09-30T21:25:07.735Z'
---

## Overview

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.

## Affected

- `active_backup_for_business_agent < 3.1.0-4967`

## Remediation

Upgrade past the affected range:

- `active_backup_for_business_agent 3.1.0-4967`