Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/{channelid}/commonteams endpoint
{
"cna_assigner": "Mattermost",
"unresolved_ranges": [
{
"source": "AFFECTED_FIELD",
"extracted_events": [
{
"introduced": "11.0.0"
},
{
"last_affected": "11.0.2"
},
{
"introduced": "10.12.0"
},
{
"last_affected": "10.12.1"
},
{
"introduced": "10.11.0"
},
{
"last_affected": "10.11.4"
},
{
"introduced": "10.5.0"
},
{
"last_affected": "10.5.12"
}
]
}
],
"cwe_ids": [
"CWE-200"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/12xxx/CVE-2025-12559.json"
}{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"source": "CPE_RANGE",
"extracted_events": [
{
"introduced": "10.5.0"
},
{
"fixed": "10.5.13"
},
{
"introduced": "10.11.0"
},
{
"fixed": "10.11.5"
},
{
"introduced": "10.12.0"
},
{
"fixed": "10.12.2"
},
{
"introduced": "11.0.0"
},
{
"fixed": "11.0.3"
}
]
}