How severe is CVE-2017-18919?

CVE-2017-18919 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2017-18919 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-18919?

CVE-2017-18919 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-18919?

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

When was CVE-2017-18919 published?

CVE-2017-18919 was published on 2020-06-19 and last updated on 2026-06-17.

CVE-2017-18919

CVE-2017-18919 is a medium-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 5.3. 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: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Mattermost Mattermost Server
Published: 2020-06-19
Last modified: 2026-06-17

Description

An issue was discovered in Mattermost Server before 3.7.0 and 3.6.3. Attackers can use the API for unauthenticated team creation.

Frequently asked questions

What is CVE-2017-18919?: An issue was discovered in Mattermost Server before 3.7.0 and 3.6.3. Attackers can use the API for unauthenticated team creation.
How severe is CVE-2017-18919?: CVE-2017-18919 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2017-18919 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-18919?: CVE-2017-18919 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-18919?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-18919 published?: CVE-2017-18919 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_server:*:*:*:*:*:*:*:*

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