CVE-2026-40539CWE-295

CVE-2026-40539

High · published September 18, 2026

CVSS v3.1
7.1
EPSS
0%
Percentile
1.6
In the wild
Unconfirmed
What it is

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 record
Technical detail
CVSS v3.1
7.1 · HIGH
Vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00117 · 1.6th percentile
Weakness
CWE-295 · Improper Certificate Validation
Published
2026-09-18T13:16Z
References (1)
https://www.synology.com/en-global/security/advisory/Synology_SA_26_06 · [email protected]
EPSS history
Timeline
  • 19 SEP 03:52Z
    EPSS moved — → 0%
    epss
  • 18 SEP 08:29Z
    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…
    cvelistv5