Security readout for executives and security teams
Plain-English summary
Synology Active Backup for Business Agent versions before 3.1.0-4967 have an installation-time origin validation flaw. A local user could cause limited arbitrary file writes and denial of service during installation. This is not described as remotely exploitable, but it can disrupt backup-agent deployment or endpoint availability.
Executive priority
Treat as a timely patching issue for managed endpoints, not an emergency remote-compromise event. Prioritize assets where backup-agent availability supports recovery, compliance, or incident response readiness.
Technical view
CVE-2025-66592 is a CWE-346 origin validation error in Synology Active Backup for Business Agent before 3.1.0-4967. CVSS 3.1 is 6.1 with local attack vector, low complexity, no privileges, user interaction required, no confidentiality impact, low integrity impact, and high availability impact.
Likely exposure
Systems running Synology Active Backup for Business Agent before 3.1.0-4967 are the stated exposure. Risk is most relevant on endpoints where untrusted local users can be present during installation or update workflows.
Exploitation context
The source bundle does not show KEV listing or active exploitation evidence. The vulnerability requires local access and user interaction during installation, which limits reach but can still affect operational continuity and backup-agent rollout integrity.
Researcher notes
Available sources do not provide exploit details, indicators of compromise, or a deeper root-cause description beyond origin validation during installation. Validate exposure through version inventory and installation workflow review rather than assuming network-reachable attack surface.
Mitigation direction
- Update Synology Active Backup for Business Agent to 3.1.0-4967 or later.
- Review Synology advisory SA-25:16 for current vendor instructions.
- Limit local user access during agent installation or update windows.
- Use trusted deployment tooling and verified installer sources.
- Monitor endpoints for failed or abnormal agent installations.
Validation and detection
- Inventory installed Active Backup for Business Agent versions.
- Confirm no managed endpoint remains below 3.1.0-4967.
- Review installation and update logs for abnormal failures.
- Validate agent functionality after upgrading.
- Check vendor advisory updates for revised affected versions or guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-346: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2025-66592 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H1.84.2synologyVulnerability scoring details
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- Synology-SA-25:16 Synology Active Backup for Business AgentCVE reference, synology · vendor-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Origin Validation Error
Origin Validation Error represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.