CVE-2017-18883: Mattermost Server has low entropy for authorization data as an OAuth 2.0 Service Provider

May 24, 2022 (updated December 5, 2025)

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2, when serving as an OAuth 2.0 Service Provider. There is low entropy for authorization data.

References

github.com/advisories/GHSA-w8cc-3h7q-jhc3
github.com/mattermost/mattermost
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2017-18883

Code Behaviors & Features

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