How severe is CVE-2021-47960?

CVE-2021-47960 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-47960 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47960?

CVE-2021-47960 affects Synology Ssl Vpn Client. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47960?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2021-47960 have an EU (EUVD) identifier?

Yes. CVE-2021-47960 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34777.

When was CVE-2021-47960 published?

CVE-2021-47960 was published on 2026-04-10 and last updated on 2026-06-17.

CVE-2021-47960

CVE-2021-47960 is a medium-severity vulnerability in Synology Ssl Vpn Client with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-552.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34777
Weakness: CWE-552
Affected product: Synology Ssl Vpn Client
Published: 2026-04-10
Last modified: 2026-06-17

Description

A files or directories accessible to external parties vulnerability in Synology SSL VPN Client before 1.4.5-0684 allows remote attackers to access files within the installation directory via a local HTTP server bound to the loopback interface. By leveraging user interaction with a crafted web page, attackers may retrieve sensitive files such as configuration files, certificates, and logs, leading to information disclosure.

Frequently asked questions

What is CVE-2021-47960?: A files or directories accessible to external parties vulnerability in Synology SSL VPN Client before 1.4.5-0684 allows remote attackers to access files within the installation directory via a local HTTP server bound to the loopback interface. By leveraging user interaction with a crafted web page, attackers may retrieve sensitive files such as configuration files, certificates, and logs, leading to information disclosure.
How severe is CVE-2021-47960?: CVE-2021-47960 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-47960 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47960?: CVE-2021-47960 affects Synology Ssl Vpn Client. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47960?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47960 have an EU (EUVD) identifier?: Yes. CVE-2021-47960 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34777.
When was CVE-2021-47960 published?: CVE-2021-47960 was published on 2026-04-10 and last updated on 2026-06-17.

References

https://www.synology.com/en-global/security/advisory/Synology_SA_26_05

Affected products (1)

cpe:2.3:a:synology:ssl_vpn_client:*:*:*:*:*:*:*:*

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