How severe is CVE-2020-8189?

CVE-2020-8189 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-8189 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8189?

CVE-2020-8189 affects Nextcloud Desktop. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-8189?

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

When was CVE-2020-8189 published?

CVE-2020-8189 was published on 2020-08-21 and last updated on 2026-06-17.

CVE-2020-8189

CVE-2020-8189 is a medium-severity vulnerability in Nextcloud Desktop with a CVSS 3.x base score of 5.4. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Nextcloud Desktop
Published: 2020-08-21
Last modified: 2026-06-17

Description

A cross-site scripting error in Nextcloud Desktop client 2.6.4 allowed to present any html (including local links) when responding with invalid data on the login attempt.

Frequently asked questions

What is CVE-2020-8189?: A cross-site scripting error in Nextcloud Desktop client 2.6.4 allowed to present any html (including local links) when responding with invalid data on the login attempt.
How severe is CVE-2020-8189?: CVE-2020-8189 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-8189 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8189?: CVE-2020-8189 affects Nextcloud Desktop. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-8189?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-8189 published?: CVE-2020-8189 was published on 2020-08-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:desktop:*:*:*:*:*:*:*:*

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