Insecure Password Storage in Synology SSL VPN Client
CVE-2021-47961

8.1HIGH

Key Information:

Vendor

Synology
Status
Synology Ssl Vpn Client
Vendor
CVE Published:
10 April 2026

What is CVE-2021-47961?

A vulnerability in the Synology SSL VPN Client prior to version 1.4.5-0684 allows remote attackers to access or influence the user's PIN code due to its insecure storage mechanism. This issue can lead to unauthorized modifications of VPN configuration and, when combined with user interaction, may enable attackers to intercept subsequent VPN traffic, compromising the integrity and confidentiality of the user's communications.

Affected Version(s)

Synology SSL VPN Client *

References

https://www.synology.com/en-global/security/advisory/Syno...
vendor-advisory

CVSS V3.1

Score:
8.1
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Laurent Sibilla (https://www.linkedin.com/in/lsibilla/)
.