CVE-2019-20886
CVE-2019-20886 is a high-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 7.5. 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-269.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (55th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-269
- Affected product: Mattermost Mattermost Server
- Published:
- Last modified:
Description
An issue was discovered in Mattermost Server before 5.8.0. The first user is sometimes inadvertently a system admin.
Frequently asked questions
- What is CVE-2019-20886?
- An issue was discovered in Mattermost Server before 5.8.0. The first user is sometimes inadvertently a system admin.
- How severe is CVE-2019-20886?
- CVE-2019-20886 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
- Is CVE-2019-20886 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-20886?
- CVE-2019-20886 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2019-20886?
- 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-2019-20886 published?
- CVE-2019-20886 was published on 2020-06-19 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
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