Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to strip action integration secrets from post payloads before broadcasting post-deletion web socket events and returning thread API responses, which allows an authenticated channel member to obtain server-side webhook URLs and authentication context from interactive-message posts via the post_deleted websocket event or the threads REST API.. Mattermost Advisory ID: MMSA-2026-00766
Metrics
Affected Vendors & Products
References
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|---|---|
| https://mattermost.com/security-updates |
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History
Sat, 17 Oct 2026 18:00:00 +0000
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Mattermost
Mattermost mattermost |
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Mattermost mattermost |
Fri, 16 Oct 2026 13:30:00 +0000
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ssvc
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Fri, 16 Oct 2026 07:30:00 +0000
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| Description | Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to strip action integration secrets from post payloads before broadcasting post-deletion web socket events and returning thread API responses, which allows an authenticated channel member to obtain server-side webhook URLs and authentication context from interactive-message posts via the post_deleted websocket event or the threads REST API.. Mattermost Advisory ID: MMSA-2026-00766 | |
| Title | Mattermost leaks interactive-message integration secrets to non-admin users via post-deletion events and thread reads | |
| Weaknesses | CWE-200 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: Mattermost
Published: 2026-10-16T07:06:00.580Z
Updated: 2026-10-16T11:58:36.743Z
Reserved: 2026-08-12T14:25:35.113Z
Link: CVE-2026-19621
Updated: 2026-10-16T11:58:30.363Z
Status : Awaiting Analysis
Published: 2026-10-16T08:17:13.390
Modified: 2026-10-16T19:23:18.623
Link: CVE-2026-19621
No data.