Mattermost versions 10.11.x <= 10.11.10 fail to properly validate permission requirements in the team member roles API endpoint which allows team administrators to demote members to guest role. Mattermost Advisory ID: MMSA-2025-00531
{
"cwe_ids": [
"CWE-863"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26230.json",
"cna_assigner": "Mattermost",
"unresolved_ranges": [
{
"source": "AFFECTED_FIELD",
"extracted_events": [
{
"introduced": "10.11.0"
},
{
"last_affected": "10.11.10"
}
]
}
]
}