CVE-2025-21088: Mattermost Incorrect Type Conversion or Cast

January 15, 2025 (updated January 17, 2025)

Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 fail to properly validate the style of proto supplied to an action’s style in post.props.attachments, which allows an attacker to crash the frontend via crafted malicious input.

References

github.com/advisories/GHSA-8j3q-gc9x-7972
github.com/mattermost/mattermost
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2025-21088
pkg.go.dev/vuln/GO-2025-3393

Code Behaviors & Features

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