CVE-2026-10103 (GCVE-0-2026-10103)
Vulnerability from cvelistv5
Published
2026-07-13 07:57
Modified
2026-07-14 14:32
Severity ?
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Summary
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
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.7.0   ≤ 11.7.2
Version: 11.6.0   ≤ 11.6.4
Version: 10.11.0   ≤ 10.11.19
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