synced 6 MIN AGO
01 Record

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

MediumPUBLISHEDCNA: synology
CNA base score6.1 CVSS v3.xCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H

02 Description

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

03 Exploitation and scoring

Exploitation
Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
SSVC decision
  • ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
  • AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
  • Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.
EPSS probability
0.08% probability of exploitation activity in the next 30 days.
EPSS percentile
Equal to or higher than the score of 0.3% of scored records. A rank, not a probability.
NVD base score
5.6 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:H
NVD analysis status
Analyzed. NVD last modified this record on 2026-10-07.
Red Hat severity
No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published
2026-05-27 08:43Z5 MO AGO
Last updated
2026-06-02 08:20Z4 MO AGO
Reserved
2025-12-05
Assigning CNA
synology
Record state
PUBLISHED
Severity
Medium (CVSS 6.1)
CNA CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Weaknesses
  • CWE-346Origin Validation ErrorClass
Data version
5.2
Document digest
a81e8dbe68b8cce8315dabc98c2c8b2fca5ff860e2f1ab6eebb8575dbb426d5a

05 Affected products

VendorProductVersionsPlatforms
SynologySynology Active Backup for Business Agent* to < 3.1.0-4967—

06 References