How severe is CVE-2020-27651?

CVE-2020-27651 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2020-27651 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27651?

CVE-2020-27651 affects Synology Router Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27651?

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

When was CVE-2020-27651 published?

CVE-2020-27651 was published on 2020-10-29 and last updated on 2026-06-17.

CVE-2020-27651

CVE-2020-27651 is a medium-severity vulnerability in Synology Router Manager with a CVSS 3.x base score of 5.8. 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-311.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-311
Affected product: Synology Router Manager
Published: 2020-10-29
Last modified: 2026-06-17

Description

Synology Router Manager (SRM) before 1.2.4-8081 does not set the Secure flag for the session cookie in an HTTPS session, which makes it easier for remote attackers to capture this cookie by intercepting its transmission within an HTTP session.

Frequently asked questions

What is CVE-2020-27651?: Synology Router Manager (SRM) before 1.2.4-8081 does not set the Secure flag for the session cookie in an HTTPS session, which makes it easier for remote attackers to capture this cookie by intercepting its transmission within an HTTP session.
How severe is CVE-2020-27651?: CVE-2020-27651 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2020-27651 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27651?: CVE-2020-27651 affects Synology Router Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27651?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-27651 published?: CVE-2020-27651 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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