CVE-2026-40539 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Adjacent Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00076.

Exploitation none

Automatable no

Technical Impact total

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://www.synology.com/en-global/security/advisory/Synology_SA_26_06

History

Fri, 18 Sep 2026 11:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Fri, 18 Sep 2026 08:45:00 +0000

Type	Values Removed	Values Added
Description		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.
Weaknesses		CWE-295
References		https://www.synology.com/en-global/security/advisory/Synology_SA_26_06
Metrics		cvssV3_1 `{'score': 7.1, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: synology

Published: 2026-09-18T08:29:33.365Z

Updated: 2026-09-18T10:40:16.842Z

Reserved: 2026-04-14T01:01:14.607Z

Link: CVE-2026-40539

Vulnrichment

Updated: 2026-09-18T10:39:56.419Z

NVD

Status : Received

Published: 2026-09-18T09:16:41.423

Modified: 2026-09-18T11:17:13.687

Link: CVE-2026-40539

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-295

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