Admin RCE via Malicious Plugin Upload on CI Test Instances
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-2462
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 10:23 UTC · Revision 1
Source evidence
Admin RCE via Malicious Plugin Upload on CI Test Instances
core-osv · Original sourcePublished 16 Mar 2026, 12:00 UTC
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528
osv:CVE-2026-2462
Complete source record
{
"id": "62a9226d001d19305035338c072300f5021eb32d930fb64f1f6ca4872af39303",
"url": "https://osv.dev/vulnerability/CVE-2026-2462",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Admin RCE via Malicious Plugin Upload on CI Test Instances",
"summary": "Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528",
"evidence": "osv:CVE-2026-2462",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-2462",
"aliases": [
"CVE-2026-2462"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/mattermost/mattermost",
"type": "GIT",
"events": [
{
"introduced": "5b955468ea1ea8b56c0fb10feb258a36a767d7bb"
},
{
"fixed": "fddd4a70bcb32eaff394a2fa5399efcd1b2ae251"
},
{
"introduced": "ab7b138824c61fe1fe815243d7e2a914dec49c8b"
},
{
"fixed": "005521aa79666e6960bc3302f6172b810f6bff3a"
},
{
"introduced": "d27a2195068ddfa3ce17cf470f9739e4edb94b83"
},
{
"fixed": "4082c3dcf285e4d1a386d2ef37f14f39dc5a0094"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "10.11.0"
},
{
"fixed": "10.11.11"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "11.2.0"
},
{
"fixed": "11.2.3"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "11.3.0"
},
{
"fixed": "11.3.1"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v10.11.11-rc1",
"v11.3.1-rc1",
"v10.11.10",
"v11.2.2",
"v11.3.0-rc4",
"v11.3.0-rc3",
"v11.3.0",
"mattermost-redux@11.3.0",
"@mattermost/types@11.3.0",
"@mattermost/client@11.3.0",
"v10.11.9",
"v11.2.1",
"v11.2.1-rc1",
"v11.2.0",
"v10.11.9-rc1",
"v10.11.8",
"v10.11.7",
"v10.11.6",
"v10.11.5",
"v10.11.4-rc3",
"v10.11.4",
"v10.11.4-rc2",
"v10.11.4-rc1",
"v10.11.3",
"v10.11.2-rc2",
"v10.11.2",
"v10.11.2-rc1",
"v10.11.1",
"v10.11.1-rc1",
"v10.11.0-rc3",
"v10.11.0",
"mattermost-redux@10.11.0",
"@mattermost/types@10.11.0",
"@mattermost/client@10.11.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-2462.json"
}
}
],
"modified": "2026-10-28T02:30:27.742321797Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/2xxx/CVE-2026-2462.json",
"https://mattermost.com/security-updates",
"https://nvd.nist.gov/vuln/detail/CVE-2026-2462"
],
"provider_metadata": {
"cwe_ids": [
"CWE-863"
],
"cna_assigner": "Mattermost",
"unresolved_ranges": [
{
"extracted_events": [
{
"range": [
{
"introduced": "11.3.0"
},
{
"last_affected": "11.3.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandaloneSingleVersion"
}
]
},
{
"extracted_events": [
{
"range": [
{
"introduced": "11.2.0"
},
{
"last_affected": "11.2.2"
},
{
"introduced": "10.11.0"
},
{
"last_affected": "10.11.10"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
}
]
}
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/2xxx/CVE-2026-2462.json"
}
},
"related_cves": [
{
"value": "CVE-2026-2462",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 494460,
"published_at": "2026-03-16T12:00:21.069+00:00"
}