How severe is CVE-2019-20860?

CVE-2019-20860 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-20860 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-20860?

CVE-2019-20860 primarily affects Mattermost Mattermost Server. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-20860?

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

When was CVE-2019-20860 published?

CVE-2019-20860 was published on 2020-06-19 and last updated on 2026-06-17.

CVE-2019-20860

CVE-2019-20860 is a medium-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mattermost Mattermost Server
Published: 2020-06-19
Last modified: 2026-06-17

Description

An issue was discovered in Mattermost Server before 5.14.0, 5.13.3, 5.12.6, and 5.9.4. It allows remote attackers to cause a denial of service (application hang) via a crafted SVG document.

Frequently asked questions

What is CVE-2019-20860?: An issue was discovered in Mattermost Server before 5.14.0, 5.13.3, 5.12.6, and 5.9.4. It allows remote attackers to cause a denial of service (application hang) via a crafted SVG document.
How severe is CVE-2019-20860?: CVE-2019-20860 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2019-20860 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-20860?: CVE-2019-20860 primarily affects Mattermost Mattermost Server. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-20860?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-20860 published?: CVE-2019-20860 was published on 2020-06-19 and last updated on 2026-06-17.

References

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

Affected products (6)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
cpe:2.3:a:mattermost:mattermost_server:5.14.0:rc1:*:*:*:*:*:*
cpe:2.3:a:mattermost:mattermost_server:5.14.0:rc2:*:*:*:*:*:*
cpe:2.3:a:mattermost:mattermost_server:5.14.0:rc3:*:*:*:*:*:*
cpe:2.3:a:mattermost:mattermost_server:5.14.0:rc4:*:*:*:*:*:*
cpe:2.3:a:mattermost:mattermost_server:5.14.0:rc5:*:*:*:*:*:*

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