Description
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to verify post ownership in the shared channel inbound sync handler, which allows an authenticated remote cluster to modify or delete posts authored by local users or other remotes via crafted sync messages referencing arbitrary post IDs in channels shared with that remote.. Mattermost Advisory ID: MMSA-2026-00689
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
Vendor Solution
Update Mattermost to versions 11.8.0, 11.7.3, 11.6.5, 10.11.20 or higher.
Tracking
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Advisories
No advisories yet.
References
| Link | Providers |
|---|---|
| https://mattermost.com/security-updates |
|
History
Mon, 13 Jul 2026 09:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Mattermost
Mattermost mattermost |
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| Vendors & Products |
Mattermost
Mattermost mattermost |
Mon, 13 Jul 2026 08:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to verify post ownership in the shared channel inbound sync handler, which allows an authenticated remote cluster to modify or delete posts authored by local users or other remotes via crafted sync messages referencing arbitrary post IDs in channels shared with that remote.. Mattermost Advisory ID: MMSA-2026-00689 | |
| Title | Authenticated remote cluster can modify or delete posts it does not own in Mattermost Connected Workspaces shared channels | |
| Weaknesses | CWE-639 | |
| References |
| |
| Metrics |
cvssV3_1
|
Status: PUBLISHED
Assigner: Mattermost
Published:
Updated: 2026-07-13T07:57:11.062Z
Reserved: 2026-05-29T15:37:04.097Z
Link: CVE-2026-10103
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OpenCVE Enrichment
Updated: 2026-07-13T09:30:04Z
Weaknesses