CVE-2020-14457: Mattermost Server Sensitive Data Exposure

May 24, 2022 (updated August 14, 2025)

An issue was discovered in Mattermost Server before 5.20.0. Non-members can receive broadcasted team details via the update_team WebSocket event, aka MMSA-2020-0012.

References

github.com/advisories/GHSA-j2h2-cvwh-cr64
github.com/mattermost/mattermost
github.com/mattermost/mattermost/pull/13848
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2020-14457

Code Behaviors & Features

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