CVE-2021-26566
CVSS v3
9
CRITICAL
EPSS Score
1.5 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
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.
Technical details
- Published
- 2021-02-26
Frequently asked questions
What is CVE-2021-26566?
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.
Is CVE-2021-26566 actively exploited?
Active exploitation of CVE-2021-26566 has not been confirmed. Its EPSS score was 1.5% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-26566?
CVE-2021-26566 has a CVSS v3 base score of 9 (CRITICAL severity).
Is CVE-2021-26566 affecting your environment?
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