Authentication Bypass by Primary Weakness Affecting github.com/mattermost/mattermost/server/v8/channels/api4 package, versions >=11.6.0 <11.6.5>=11.7.0 <11.7.3>=11.8.0-rc1 <11.8.0-rc4
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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Test your applications- Snyk IDSNYK-GOLANG-GITHUBCOMMATTERMOSTMATTERMOSTSERVERV8CHANNELSAPI4-17966794
- published14 Jul 2026
- disclosed13 Jul 2026
- creditUnknown
Introduced: 13 Jul 2026
NewCVE-2026-9597 (opens in a new tab)How to fix?
Upgrade github.com/mattermost/mattermost/server/v8/channels/api4 to version 11.6.5, 11.7.3, 11.8.0-rc4 or higher.
Overview
github.com/mattermost/mattermost/server/v8/channels/api4 is a platform for secure collaboration across the entire software development lifecycle
Affected versions of this package are vulnerable to Authentication Bypass by Primary Weakness in the magic-link token authentication process. An attacker can gain unauthorized access to a deactivated guest account by using a previously issued magic-link token.