Synology DiskStation Manager up to 7.2.0/7.2.2-72806-6/7.3.2-86009-1 Email API certificate validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.39

Summaryinfo

A vulnerability described as problematic has been identified in Synology DiskStation Manager up to 7.2.0/7.2.2-72806-6/7.3.2-86009-1. Affected by this vulnerability is an unknown functionality of the component Email API. Executing a manipulation can lead to certificate validation. This vulnerability is registered as CVE-2026-40539. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic was found in Synology DiskStation Manager up to 7.2.0/7.2.2-72806-6/7.3.2-86009-1. This vulnerability affects an unknown code block of the component Email API. The manipulation with an unknown input leads to a certificate validation vulnerability. The CWE definition for the vulnerability is CWE-295. The product does not validate, or incorrectly validates, a certificate. As an impact it is known to affect integrity. CVE summarizes:

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.

The advisory is shared for download at synology.com. This vulnerability was named CVE-2026-40539 since 04/14/2026. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1587.003.

Upgrading to version 7.2.1-69057-10, 7.2.2-72806-7 or 7.3.2-86009-2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-82797). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.1
CNA Vector (synology): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: DiskStation Manager 7.2.1-69057-10/7.2.2-72806-7/7.3.2-86009-2

Timelineinfo

04/14/2026 CVE reserved
09/18/2026 +157 days Advisory disclosed
09/18/2026 +0 days VulDB entry created
09/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: synology.com

Advisory: synology.com
Status: Confirmed

CVE: CVE-2026-40539 (🔒)
GCVE (CVE): GCVE-0-2026-40539
GCVE (VulDB): GCVE-100-407440
EUVD: 🔒

Entryinfo

Created: 09/18/2026 10:51
Updated: 09/18/2026 11:19
Changes: 09/18/2026 10:51 (64), 09/18/2026 11:19 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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