CVE-2026-40539: An improper certificate validation vulnerability in Email API in Synology DiskStation Manager (DSM) before 7.2.1-69057-10, 7.2.2-72806-7 and 7.3.2-86009-2…

PriorityP433high7.1CVSS 3.1

AVAACHPRNUIRSUCHIHAH

EPSS

0.08%

0.1th percentile

An improper certificate validation vulnerability in Email API in Synology DiskStation Manager (DSM) before 7.2.1-69057-10, 7.2.2-72806-7 and 7.3.2-86009-2 allows man-in-the-middle attackers to read or write arbitrary files and conduct denial-of-service attacks.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
synology	diskstation_manager	>= 7.2.1 < 7.2.1-69057-10	7.2.1-69057-10
synology	diskstation_manager	>= 7.2.2 < 7.2.2-72806-7	7.2.2-72806-7
synology	diskstation_manager	>= 7.3 < 7.3.2-86009-2	7.3.2-86009-2

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