title: HTML Injection while inviting Guests
description: Mattermost 6.3.0 and earlier fails to properly sanitize the HTML content in the email invitation sent to guest users, which allows registered users with special permissions to invite guest users to inject unescaped HTML content in the email invitations.
problem types: CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
affected:
{
product: Mattermost
vendor: Mattermost
versions:
lessThanOrEqual: 6.3, status: affected, version: unspecified, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 2
baseSeverity: LOW
confidentialityImpact: NONE
integrityImpact: LOW
privilegesRequired: HIGH
scope: UNCHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:L/A:N
version: 3.1
]
solutions: Update Mattermost to version v6.4 or higher