How severe is CVE-2020-27488?

CVE-2020-27488 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-27488 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27488?

CVE-2020-27488 affects Loxone Miniserver Gen 1 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27488?

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

When was CVE-2020-27488 published?

CVE-2020-27488 was published on 2021-01-13 and last updated on 2026-06-17.

CVE-2020-27488

CVE-2020-27488 is a critical-severity vulnerability in Loxone Miniserver Gen 1 Firmware with a CVSS 3.x base score of 9.8. 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-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Loxone Miniserver Gen 1 Firmware
Published: 2021-01-13
Last modified: 2026-06-17

Description

Loxone Miniserver devices with firmware before 11.1 (aka 11.1.9.3) are unable to use an authentication method that is based on the "signature of the update package." Therefore, these devices (or attackers who are spoofing these devices) can continue to use an unauthenticated cloud service for an indeterminate time period (possibly forever). Once an individual device's firmware is updated, and authentication occurs once, the cloud service recategorizes the device so that authentication is subsequently always required, and spoofing cannot occur.

Frequently asked questions

What is CVE-2020-27488?: Loxone Miniserver devices with firmware before 11.1 (aka 11.1.9.3) are unable to use an authentication method that is based on the "signature of the update package." Therefore, these devices (or attackers who are spoofing these devices) can continue to use an unauthenticated cloud service for an indeterminate time period (possibly forever). Once an individual device's firmware is updated, and authentication occurs once, the cloud service recategorizes the device so that authentication is subsequently always required, and spoofing cannot occur.
How severe is CVE-2020-27488?: CVE-2020-27488 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-27488 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27488?: CVE-2020-27488 affects Loxone Miniserver Gen 1 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27488?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-27488 published?: CVE-2020-27488 was published on 2021-01-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:loxone:miniserver_gen_1_firmware:*:*:*:*:*:*:*:*

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