What’s Vulnerable › Vulnerabilities
CVE-2019-20887
- Severity: medium (CVSS 4.3 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.7% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2020-06-19 · updated 2026-06-17
- Weakness: CWE-862
Description
An issue was discovered in Mattermost Server before 5.7.1, 5.6.4, 5.5.3, and 4.10.6. It does not honor flags API permissions when deciding whether a user can receive intra-team posts.
Affected products
- Mattermost: before 4.10.6; from 5.5.0 before 5.5.3; from 5.6.0 before 5.6.4; from 5.7.0 before 5.7.1 — fixed in 4.10.6, 5.5.3, 5.6.4, 5.7.1
How to fix
Upgrade to a fixed version: Mattermost 4.10.6, 5.5.3, 5.6.4, 5.7.1. Check the vendor advisory for mitigations.
References
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