{"id":"CVE-2026-93846","kind":"vulnerability","aliases":["CVE-2026-93846"],"related":[],"title":"Mattermost: team admins can grant members roles beyond the permission scheme","description":"Mattermost versions 11.7.x <= 11.7.10 fail to restrict which built-in roles can be assigned to a team member via the API, which allows a team admin to grant a team member permissions beyond those permitted by the configured permission scheme via the {{update-team-member-roles}} REST API.. Mattermost Advisory ID: MMSA-2026-00734","summary":"Mattermost versions 11.7.x up to 11.7.10 do not restrict which built-in roles a team admin can assign to a team member through the update-team-member-roles API. A team admin can therefore give a member more permissions than the configured permission scheme allows.","severity":"low","cvss":3.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["mattermost","runtime","self-hosted"],"not_affected_if":["default-config"],"how_to_check":"- Check the running Mattermost version in the System Console or with `mattermost version` on the server; affected versions are `11.7.0` through `11.7.10`.","fix":"- Upgrade Mattermost to a release containing the fix for MMSA-2026-00734 (the sources do not name the patched version; unknown).","status":"open","published_at":"2026-10-26T16:17:23+00:00","first_seen_at":"2026-10-26T16:31:01+00:00","triaged_at":"2026-10-26T16:33:03+00:00","updated_at":"2026-10-26T16:33:03+00:00","category":"runtime","confidence":0.6,"triage":{"at":"2026-10-26T16:33:03Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Mattermost to a release containing the fix for MMSA-2026-00734 (the sources do not name the patched version; unknown).","reach":"network","title":"Mattermost: team admins can grant members roles beyond the permission scheme","impact":"medium","summary":"Mattermost versions 11.7.x up to 11.7.10 do not restrict which built-in roles a team admin can assign to a team member through the update-team-member-roles API. A team admin can therefore give a member more permissions than the configured permission scheme allows.","category":"runtime","nicknames":[],"who_cares":["mattermost","self-hosted"],"confidence":0.6,"needs_auth":"yes","worst_case":"A team admin grants a member permissions beyond the permission scheme","analyst_note":"Find the patched Mattermost version and the exact affected range in MMSA-2026-00734 and the NVD entry.","how_to_check":"- Check the running Mattermost version in the System Console or with `mattermost version` on the server; affected versions are `11.7.0` through `11.7.10`.","needs_analyst":true,"not_affected_if":["default-config"],"who_is_affected":"Self-hosted or managed Mattermost servers on the 11.7.x line up to 11.7.10 where team admins exist and a permission scheme limits built-in roles. Exposure depends on a team admin being the one who escalates, so servers with no delegated team admins face less risk. Installations already on a fixed release can skip it.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"low"},"cost_usd":0.000605,"input_tokens":3345,"output_tokens":541,"severity_before":"low"},"analyst_status":null,"analyst_note":null,"search":"'-00734':128C '-2026':13A,16A,127C '-93846':14A,17A '..':122C '11.7':25B,73C '11.7.10':29B,75C 'admin':3A,40B,57B,98C 'advisori':124C 'allow':70B,95C 'api':54B,93C,121C 'assign':42B,86C 'beyond':8A,105C 'built':35B,81C 'built-in':34B,80C 'configur':67B,110C 'cve':12A,15A 'fail':76C 'give':60B 'grant':5A,100C 'host':22B 'id':125C 'mattermost':1A,18B,23B,71C,123C 'member':6A,46B,52B,62B,90C,103C,118C 'mmsa':126C 'permiss':10A,64B,68B,104C,111C 'permit':107C 'rest':120C 'restrict':32B,78C 'role':7A,37B,53B,83C,119C 'runtim':19B 'scheme':11A,69B,112C 'self':21B 'self-host':20B 'team':2A,39B,45B,51B,56B,89C,97C,102C,117C 'therefor':59B 'updat':50B,116C 'update-team-member-rol':49B,115C 'version':24B,72C 'via':91C,113C 'x':26B,74C","nicknames":[],"mitigations":[],"who_affected":"Self-hosted or managed Mattermost servers on the 11.7.x line up to 11.7.10 where team admins exist and a permission scheme limits built-in roles. Exposure depends on a team admin being the one who escalates, so servers with no delegated team admins face less risk. Installations already on a fixed release can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-26T16:17:23+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N","cvss_by":"responsibledisclosure@mattermost.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-93846","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93846","severity":null,"published_at":"2026-10-26T16:17:23+00:00","modified_at":"2026-10-26T16:17:23+00:00","first_seen_at":"2026-10-26T16:31:01+00:00","fetched_at":"2026-10-26T16:31:01+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}