CVE-2021-47961

highpriority · track · 0EPSS 0.003 · 25 %ileEUNLRUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.32% (25th) EPSS

CVSS 8.1 · high

Is it mine?

4 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · ncsc_nl

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

8.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.18.1highAV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Nsecondary · FSTEC (BDU) RU

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Nsecondary · ENISA EU

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Nsecondary · security@synology.comexploitability 2.8 · impact 5.2

v3.17.4highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Nsecondary · NCSC-NL NL

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-256USCWE-256USCWE-256US

affected products (4)

Products and version ranges known to be affected.

Synology Synology SSL VPN Client* → 1.4.5-0684enisa_euvdEU
Synology Inc. Synology SSL VPN Client≤ 1.4.5-0684fstec_bduRU
Synology Synology SSL VPN Client≤ vers:unknown/*ncsc_nlNL
synology ssl vpn client< 1.4.5-0684nvdUScpe:2.3:a:synology:ssl_vpn_client:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

NCSC-2026-0109Kwetsbaarheden verholpen in Synology SSL VPN ClientNL2026-04-10csaf · ncsc_nlNL
Synology heeft kwetsbaarheden verholpen in Synology SSL VPN Client.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu ncsc_nl nvd NVD CVE.org MITRE

published 2026-04-10modified 2026-06-17

references (3)

External citations — patches, advisories, analysis.

scry

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