title: Lack of restriction to manage group names for freshly demoted guests
description: Mattermost fails to update the permissions of the current session for a user who was just demoted to guest, allowing freshly demoted guests to change group names.
problem types: CWE-284: Improper Access Control
affected:
{
defaultStatus: unaffected
product: Mattermost
vendor: Mattermost
versions:
lessThanOrEqual: 9.2.2, status: affected, version: 0, versionType: semver
lessThanOrEqual: 8.1.6, status: affected, version: 0, versionType: semver
status: unaffected, version: 8.1.7
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 3.7
baseSeverity: LOW
confidentialityImpact: NONE
integrityImpact: LOW
privilegesRequired: LOW
scope: UNCHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:L
version: 3.1
]
format: CVSS
scenarios: GENERAL
solutions: Update Mattermost Server to versions 8.1.7, 9.3.0 or higher.