CVE-2020-27648

Name: CVE-2020-27648
Creator: NVD / NIST
Published: 2020-10-29T09:15:12.573+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9/10EPSS 0.71%

Last modified Jun 17, 2026

CVE-2020-27648 is a critical-severity vulnerability rated 9/10 on the CVSS scale. Improper certificate validation vulnerability in OpenVPN client in Synology DiskStation Manager (DSM) before 6.2.3-25426-2 allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.. EPSS estimates a 0.71% chance of exploitation in the next 30 days.

Description

Improper certificate validation vulnerability in OpenVPN client in Synology DiskStation Manager (DSM) before 6.2.3-25426-2 allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

Metrics

CVSS 3.1

9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

EPSS Probability

0.71%

48.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Synology	Diskstation Manager	>= 6.2, < 6.2.3-25426-2
Synology	Skynas Firmware	< 6.2.3-25426

References

https://www.synology.com/security/advisory/Synology_SA_20_18Vendor Advisory
https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1058Exploit, Third Party Advisory
https://www.synology.com/security/advisory/Synology_SA_20_18Vendor Advisory
https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1058Exploit, Third Party Advisory

Timeline

Published: Oct 29, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-27648?

How severe is CVE-2020-27648?

CVE-2020-27648 has a CVSS score of 9/10 (CRITICAL severity). The EPSS model estimates a 0.71% probability of exploitation in the next 30 days.

How do I fix CVE-2020-27648?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-27648?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST