Home/CVE/Insertion of sensitive information into sent data vulnerability in synorelayd in Synology DiskStation Manager (DSM) befo
CVE

CVE-2021-26566

Insertion of sensitive information into sent data vulnerability in synorelayd in Synology DiskStation Manager (DSM) befo

Insertion of sensitive information into sent data vulnerability in synorelayd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to execute arbitrary commands via inbound QuickConnect traffic.

HIGH · CVSS 8.3 EPSS 0.00535
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  • Public exploit or PoC is available
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-201Insertion of Sensitive Information Into Sent Data
▤

Affected Products & Versions

4
synology diskstation manager< 6.2.3-25426-3
synology vs960hd firmwareall versions
synology skynas firmwareall versions
synology diskstation manager unified controllerall versions
⚠

Public Exploits & PoCs

1
pocwww.talosintelligence.com · TALOS-2020-1160www.talosintelligence.com
▣

Scoring & Timeline

8.3
HIGH · CVSS v3.1 · security@synology.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD26 Feb 2021 · 10:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H
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References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://www.synology.com/security/advisory/Synology_SA_20_26Vendor Advisory
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