title: Information disclosure in linked message previews
description: Mattermost allows an attacker to request a preview of an existing message when creating a new message via the createPost API call, disclosing the contents of the linked message.
problem types: CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
affected:
{
defaultStatus: unaffected
product: Mattermost
vendor: Mattermost
versions:
lessThanOrEqual: 7.7.1, status: affected, version: 6.3.0, versionType: semver
lessThanOrEqual: 7.1.5, status: affected, version: 6.3.0, versionType: semver
lessThanOrEqual: 7.8.0, status: affected, version: 6.3.0, versionType: semver
status: unaffected, version: 7.8.1
status: unaffected, version: 7.7.2
status: unaffected, version: 7.1.6
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 6.5
baseSeverity: MEDIUM
confidentialityImpact: HIGH
integrityImpact: NONE
privilegesRequired: LOW
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
version: 3.1
]
format: CVSS
scenarios: GENERAL
solutions: Update Mattermost to version v7.8.0, v7.1.6, v7.7.2, or higher.