What’s Vulnerable › Vulnerabilities
CVE-2017-18894
- Severity: high (CVSS 8.1 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.8% 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-732
Description
An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. Sometimes. resource-owner authorization is bypassed, allowing account takeover.
Affected products
- Mattermost: before 4.0.5; from 4.1.0 before 4.1.1; 4.2.0-rc1, 4.2.0-rc2, 4.2.0-rc3, 4.2.0-rc4 — fixed in 4.0.5, 4.1.1
How to fix
Upgrade to a fixed version: Mattermost 4.0.5, 4.1.1. Check the vendor advisory for mitigations.
References
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