Incorrect Authorization Affecting github.com/mattermost/mattermost/server/channels/app package, versions >=10.11.0-rc1 <10.11.14-rc1>=11.4.0-rc1 <11.4.4>=11.5.0-rc1 <11.5.2-rc1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-GOLANG-GITHUBCOMMATTERMOSTMATTERMOSTSERVERCHANNELSAPP-16873667
- published24 May 2026
- disclosed18 May 2026
- creditmr_anksec
Introduced: 18 May 2026
CVE-2026-28732 (opens in a new tab)How to fix?
Upgrade github.com/mattermost/mattermost/server/channels/app to version 10.11.14-rc1, 11.4.4, 11.5.2-rc1 or higher.
Overview
github.com/mattermost/mattermost/server/channels/app is a private-cloud Slack alternative
Affected versions of this package are vulnerable to Incorrect Authorization via the command update API. An attacker can impersonate existing system or custom commands by editing their own slash command trigger to match an already-registered trigger, potentially hijacking command functionality.