How severe is CVE-2020-27649?

CVE-2020-27649 has a CVSS 3.x base score of 8.3, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-27649 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27649?

CVE-2020-27649 affects Synology Router Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27649?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-27649 published?

CVE-2020-27649 was published on 2020-10-29 and last updated on 2026-06-17.

CVE-2020-27649

CVE-2020-27649 is a high-severity vulnerability in Synology Router Manager with a CVSS 3.x base score of 8.3. 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-295.

Key facts

Severity: High (CVSS 3.x base score 8.3)
CVSS v2: 6.8
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Synology Router Manager
Published: 2020-10-29
Last modified: 2026-06-17

Description

Improper certificate validation vulnerability in OpenVPN client in Synology Router Manager (SRM) before 1.2.4-8081 allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

Frequently asked questions

What is CVE-2020-27649?: Improper certificate validation vulnerability in OpenVPN client in Synology Router Manager (SRM) before 1.2.4-8081 allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.
How severe is CVE-2020-27649?: CVE-2020-27649 has a CVSS 3.x base score of 8.3, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-27649 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27649?: CVE-2020-27649 affects Synology Router Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27649?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-27649 published?: CVE-2020-27649 was published on 2020-10-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:synology:router_manager:*:*:*:*:*:*:*:*

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