Medium
Security advisory
An issue was discovered in Mattermost Server before 5.7. It allows a bypass of e-mail address discovery restrictions.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2019-20890
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 08:14 UTC · Revision 1
Source evidence
An issue was discovered in Mattermost Server before 5.7. It allows a bypass of e-mail address discovery restrictions.
osv:CVE-2019-20890
Complete source record
{
"id": "d23f17066e6babf004c0c6b1fe421b21f877aebe3be4627db5a04bef790d7c08",
"url": "https://osv.dev/vulnerability/CVE-2019-20890",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2019-20890",
"summary": "An issue was discovered in Mattermost Server before 5.7. It allows a bypass of e-mail address discovery restrictions.",
"evidence": "osv:CVE-2019-20890",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2019-20890",
"aliases": [
"CVE-2019-20890"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/mattermost/mattermost",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "7e5fda43bda67cd061e527b64046f241c2d6cc32"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "5.7.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v5.7.0-rc5",
"v5.7.0-rc4",
"v5.7.0-rc3",
"v5.7.0-rc2",
"v5.7.0-rc1",
"v5.6.1-rc3",
"v5.6.1-rc2",
"v5.6.1-rc1",
"v5.6.1",
"v5.6.0-rc6",
"v5.6.0",
"v5.6.0-rc5",
"v5.6.0-rc4",
"v5.6.0-rc3",
"v5.6.0-rc2",
"v5.6.0-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-2019-20890.json"
}
}
],
"modified": "2026-10-24T10:31:04.711038352Z",
"provider": "osv",
"references": [
"https://mattermost.com/security-updates/"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2019-20890",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 440588,
"published_at": "2020-06-19T17:15:14.067+00:00"
}