Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
{
"unresolved_ranges": [
{
"extracted_events": [
{
"introduced": "11.8.0"
},
{
"last_affected": "11.8.2"
},
{
"introduced": "11.7.0"
},
{
"last_affected": "11.7.6"
},
{
"introduced": "10.11.0"
},
{
"last_affected": "10.11.21"
}
],
"source": "AFFECTED_FIELD"
}
],
"cna_assigner": "Mattermost",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16048.json",
"cwe_ids": [
"CWE-863"
]
}{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"extracted_events": [
{
"introduced": "10.11.0"
},
{
"fixed": "10.11.22"
},
{
"introduced": "11.7.0"
},
{
"fixed": "11.7.7"
},
{
"introduced": "11.8.0"
},
{
"fixed": "11.8.3"
}
],
"source": "CPE_RANGE"
}