CVE-2026-40539NVD

Vulnerability Summary

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.

Severity Level

HIGH(7.1)

Published Date

Sep 18, 2026

Last Modified

Sep 18, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.08%Probability

Root Weakness (CWE)

N/A

CVSS v3.1 Base Metrics

Attack VectorAdjacent

Attack ComplexityHigh

Privileges RequiredNone

User InteractionRequired

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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