Vulnerability in Synology Diskstation Manager (Dsm)

CVE-2026-40538

An improper restriction of excessive authentication attempts vulnerability in Auto block in Synology DiskStation Manager (DSM) before 7.2.1-69057-10, 7.2.2-72806-7 and 7.3.2-86009-2 allows remote attackers to read limited files via brute-force attacks.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 3.7 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (31.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-40538: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-40538?
CVE-2026-40538 is a low-severity vulnerability in Synology Diskstation Manager (Dsm), classified under Improper Restriction of Excessive Authentication Attempts. CVSS score: 3.7/10. Published 2026-09-18.
How severe is CVE-2026-40538?
Low severity. CVSS v3 base score is 3.7 out of 10.