CVE-2017-18879: Mattermost Server is vulnerable to XSS through author_link field in Slack attachments

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. XSS could occur via the author_link field of a Slack attachment.

References

github.com/advisories/GHSA-498j-wxww-j897
github.com/mattermost/mattermost
mattermost.com/security-updates
nvd.nist.gov/vuln/detail/CVE-2017-18879

Code Behaviors & Features

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