title: Existing server guests invited to the team by members without "invite_guest" permission
description: Mattermost fails to check the "invite_guest" permission when inviting guests of other teams to a team, allowing a member with permissions to add other members but not to add guests to add a guest to a team as long as the guest was already a guest in another team of the server
problem types: CWE-284: Improper Access Control
affected:
{
defaultStatus: unaffected
product: Mattermost
vendor: Mattermost
versions:
lessThanOrEqual: 9.4.1, status: affected, version: 0, versionType: semver
lessThanOrEqual: 9.3.0, status: affected, version: 0, versionType: semver
lessThanOrEqual: 9.2.4, status: affected, version: 0, versionType: semver
lessThanOrEqual: 8.1.8, status: affected, version: 0, versionType: semver
status: unaffected, version: 9.5.0
status: unaffected, version: 9.4.2
status: unaffected, version: 9.3.1
status: unaffected, version: 9.2.5
status: unaffected, version: 8.1.9
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 4.3
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: LOW
privilegesRequired: LOW
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
version: 3.1
]
format: CVSS
scenarios: GENERAL
solutions: Update Mattermost Server to versions 9.5.0, 9.4.2, 9.3.1, 9.2.5, 8.1.9 or higher.