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.
PUBLISHED5.2CWE-295
Problem type
Affected products
Synology
DiskStation Manager (DSM)
< 7.3.2-86009-2 - AFFECTED
< 7.2.2-72806-7 - AFFECTED
< 7.2.1-69057-10 - AFFECTED
< 7.2.1 - UNKNOWN
References
GitHub Security Advisories
GHSA-mqfj-89cq-4gj9
An improper certificate validation vulnerability in Email API in Synology DiskStation Manager ...
https://github.com/advisories/GHSA-mqfj-89cq-4gj9An 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.
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-40539Click to expand
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"assignerOrgId": "db201096-a0cc-46c7-9a55-61d9e221bf01",
"assignerShortName": "synology",
"dateUpdated": "2026-09-18T08:29:33.365Z",
"dateReserved": "2026-04-14T01:01:14.607Z",
"datePublished": "2026-09-18T08:29:33.365Z",
"state": "PUBLISHED"
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}
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"affected": [
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"defaultStatus": "affected",
"versions": [
{
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"problemTypes": [
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"references": [
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"url": "https://www.synology.com/en-global/security/advisory/Synology_SA_26_06",
"name": "Synology-SA-26:06 DSM",
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"metrics": [
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"attackVector": "ADJACENT_NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "UNCHANGED",
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"baseScore": 7.1,
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"credits": [
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"value": "Ben R of Interrupt Labs (https://www.interruptlabs.co.uk)",
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}