How severe is CVE-2020-27655?

CVE-2020-27655 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2020-27655 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27655?

CVE-2020-27655 affects Synology Router Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27655?

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

When was CVE-2020-27655 published?

CVE-2020-27655 was published on 2020-10-29 and last updated on 2026-06-17.

CVE-2020-27655

CVE-2020-27655 is a medium-severity vulnerability in Synology Router Manager 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-269.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 7.5
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-269
Affected product: Synology Router Manager
Published: 2020-10-29
Last modified: 2026-06-17

Description

Improper access control vulnerability in Synology Router Manager (SRM) before 1.2.4-8081 allows remote attackers to access restricted resources via inbound QuickConnect traffic.

Frequently asked questions

What is CVE-2020-27655?: Improper access control vulnerability in Synology Router Manager (SRM) before 1.2.4-8081 allows remote attackers to access restricted resources via inbound QuickConnect traffic.
How severe is CVE-2020-27655?: CVE-2020-27655 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2020-27655 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27655?: CVE-2020-27655 affects Synology Router Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27655?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-27655 published?: CVE-2020-27655 was published on 2020-10-29 and last updated on 2026-06-17.

References

Affected products (1)

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

More vulnerabilities in Synology Router Manager

CVE-2023-32956 — Critical (CVSS 9.8): Improper neutralization of special elements used in an OS command ('OS Command Injection') vulnerability in CGI…
CVE-2020-27654 — Critical (CVSS 9.8): Improper access control vulnerability in lbd in Synology Router Manager (SRM) before 1.2.4-8081 allows remote attackers…
CVE-2018-1160 — Critical (CVSS 9.8): Netatalk before 3.1.12 is vulnerable to an out of bounds write in dsi_opensess.c. This is due to lack of bounds…
CVE-2017-14491 — Critical (CVSS 9.8): Heap-based buffer overflow in dnsmasq before 2.78 allows remote attackers to cause a denial of service (crash) or…
CVE-2019-11823 — High (CVSS 8.6): CRLF injection vulnerability in Network Center in Synology Router Manager (SRM) before 1.2.3-8017-2 allows remote…
CVE-2020-27653 — High (CVSS 8.3): Algorithm downgrade vulnerability in QuickConnect in Synology Router Manager (SRM) before 1.2.4-8081 allows…

All CVEs affecting Synology Router Manager →

Other CWE-269 (Improper Privilege Management) vulnerabilities

CVE-2026-31852 — Critical (CVSS 10.0): Jellyfin is an open-source media system. The code-quality.yml GitHub Actions workflow in jellyfin/jellyfin-ios is…
CVE-2025-20282 — Critical (CVSS 10.0): A vulnerability in an internal API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to…
CVE-2025-0505 — Critical (CVSS 10.0): On Arista CloudVision systems (virtual or physical on-premise deployments), Zero Touch Provisioning can be used to gain…
CVE-2023-48418 — Critical (CVSS 10.0): In checkDebuggingDisallowed of DeviceVersionFragment.java, there is a possible way to access adb before SUW…
CVE-2023-48419 — Critical (CVSS 10.0): An attacker in the wifi vicinity of a target Google Home can spy on the victim, resulting in Elevation of Privilege
CVE-2023-31273 — Critical (CVSS 10.0): Protection mechanism failure in some Intel DCM software before version 5.2 may allow an unauthenticated user to…

Browse all CWE-269 (Improper Privilege Management) vulnerabilities →