Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to enforce atomic single-use consumption of guest magic link tokens, which allows an attacker with access to a valid magic link to establish multiple independent authenticated sessions via concurrent requests.. Mattermost Advisory ID: MMSA-2026-00624
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/3xxx/CVE-2026-3590.json",
"cna_assigner": "Mattermost",
"cwe_ids": [
"CWE-367"
],
"unresolved_ranges": [
{
"extracted_events": [
{
"introduced": "10.11.0"
},
{
"last_affected": "10.11.12"
},
{
"introduced": "11.5.0"
},
{
"last_affected": "11.5.0"
},
{
"introduced": "11.4.0"
},
{
"last_affected": "11.4.2"
},
{
"introduced": "11.3.0"
},
{
"last_affected": "11.3.2"
}
],
"source": "AFFECTED_FIELD"
}
]
}{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"extracted_events": [
{
"introduced": "10.11.0"
},
{
"fixed": "10.11.13"
},
{
"introduced": "11.3.0"
},
{
"fixed": "11.3.3"
},
{
"introduced": "11.4.0"
},
{
"fixed": "11.4.3"
},
{
"introduced": "11.5.0"
},
{
"fixed": "11.5.1"
}
],
"source": "CPE_RANGE"
}