CVE-2026-3637Medium· 4.3▾ SunlitMattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check the create_post channel permission during post edit operations which allows an authenticated attacker with revoked posting privileges to modify the…
▾ Sunlit zone — Low / medium · no exploitation signal
impact 23.7 · likelihood 0.1 · exploitation 0
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Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.3%
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check the create_post channel permission during post edit operations which allows an authenticated attacker with revoked posting privileges to modify their existing posts via direct API requests to the post update and patch endpoints.. Mattermost Advisory ID: MMSA-2026-00627
mattermost_server >= 10.11.0, < 10.11.14mattermost_server >= 11.4.0, < 11.4.4mattermost_server >= 11.5.0, < 11.5.2Upgrade past the affected range:
mattermost_server 11.5.2Connected by shared product, vendor, weakness, or advisory.
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