High
Security advisory
An issue was discovered in Mattermost Server before 5.13.0. Incoming webhook creation is not properly restricted.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2019-20863
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 04:56 UTC · Revision 1
Source evidence
An issue was discovered in Mattermost Server before 5.13.0. Incoming webhook creation is not properly restricted.
osv:CVE-2019-20863
Complete source record
{
"id": "375347997c6e88c480c4334a2f828efe5edd28bc1d7bc902bb246c34e815ccf9",
"url": "https://osv.dev/vulnerability/CVE-2019-20863",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2019-20863",
"summary": "An issue was discovered in Mattermost Server before 5.13.0. Incoming webhook creation is not properly restricted.",
"evidence": "osv:CVE-2019-20863",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2019-20863",
"aliases": [
"CVE-2019-20863"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/mattermost/mattermost",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "f8469de7724a9449b43b514a99acefaf02430ad9"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "5.13.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v5.13.0-rc2",
"v5.13.0-rc1",
"v5.12.0-rc6",
"v5.12.0",
"v5.12.0-rc5",
"v5.12.0-rc4",
"v5.12.0-rc3",
"v5.12.0-rc2",
"v5.12.0-rc1",
"v5.2.0-rc2",
"v5.2.0-rc1",
"v5.1.0-rc1",
"v5.0.0-rc1",
"v4.10.0-rc1",
"v4.9.0-rc1",
"v4.8.0-rc1",
"v4.7.0-rc1",
"v4.6.0-rc2",
"v4.6.0-rc1",
"v4.5.0-rc1",
"v4.4.0-rc1",
"v4.3.0-rc1",
"v4.2.0-rc1",
"v0.5.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2019-20863.json"
}
}
],
"modified": "2026-10-24T10:30:23.253914062Z",
"provider": "osv",
"references": [
"https://mattermost.com/security-updates/"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2019-20863",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 430879,
"published_at": "2020-06-19T15:15:10.93+00:00"
}