How severe is CVE-2019-20861?

CVE-2019-20861 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-20861 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-20861?

CVE-2019-20861 affects Mattermost Mattermost Desktop. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-20861?

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-2019-20861 published?

CVE-2019-20861 was published on 2020-06-19 and last updated on 2026-06-17.

CVE-2019-20861

CVE-2019-20861 is a high-severity vulnerability in Mattermost Mattermost Desktop with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mattermost Mattermost Desktop
Published: 2020-06-19
Last modified: 2026-06-17

Description

An issue was discovered in Mattermost Desktop App before 4.2.2. It allows attackers to execute arbitrary code via a crafted link.

Frequently asked questions

What is CVE-2019-20861?: An issue was discovered in Mattermost Desktop App before 4.2.2. It allows attackers to execute arbitrary code via a crafted link.
How severe is CVE-2019-20861?: CVE-2019-20861 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-20861 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-20861?: CVE-2019-20861 affects Mattermost Mattermost Desktop. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-20861?: 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-2019-20861 published?: CVE-2019-20861 was published on 2020-06-19 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates/

Affected products (1)

cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*

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