8.1

CVE-2021-47961: synology ssl_vpn_client Plaintext Storage of a Password

CVSS: 8.1v3.1HighAnalyzed
Published 10-04-2026Last modified 10-04-2026
Open JSON

Vulnerability summary

CVE-2021-47961 is a high (CVSS 8.1) Plaintext Storage of a Password vulnerability in synology ssl_vpn_client. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23.8% of scored vulnerabilities.

Overall risk
32/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.32%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 10-04-2026
    PublishedVulnerability first disclosed.
  2. 10-04-2026
    Last modifiedVulnerability information updated.

Description

A plaintext storage of a password vulnerability in Synology SSL VPN Client before 1.4.5-0684 allows remote attackers to access or influence the user's PIN code due to insecure storage. This may lead to unauthorized VPN configuration and potential interception of subsequent VPN traffic when combined with user interaction.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.32%

Chance of exploitation in the next 30 days

Percentile

24%

Versus all other CVEs

30-day change

0.00 pp

From 0.32% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.32%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Synology2 products

1 vendor · 2 products

References

1 links