Low
Leaked User IDs and Metadata of Deleted DMs
Type: advisorySources: OSV
Mattermost versions 9.11.x <= 9.11.6 fail to filter out DMs from the deleted channels endpoint which allows an attacker to infer user IDs and other metadata from deleted DMs if someone had manually marked DMs as deleted in the database.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2025-0503
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 7 Nov 2026, 10:21 UTC · Revision 1
Source evidence
Leaked User IDs and Metadata of Deleted DMs
core-osv · Original sourcePublished 14 Feb 2025, 17:52 UTC
Mattermost versions 9.11.x <= 9.11.6 fail to filter out DMs from the deleted channels endpoint which allows an attacker to infer user IDs and other metadata from deleted DMs if someone had manually marked DMs as deleted in the database.
osv:CVE-2025-0503
Complete source record
{
"id": "8ddda45a90cb904b4777117942446370e7a678271977f56d53170ff697c15e2c",
"url": "https://osv.dev/vulnerability/CVE-2025-0503",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Leaked User IDs and Metadata of Deleted DMs",
"summary": "Mattermost versions 9.11.x <= 9.11.6 fail to filter out DMs from the deleted channels endpoint which allows an attacker to infer user IDs and other metadata from deleted DMs if someone had manually marked DMs as deleted in the database.",
"evidence": "osv:CVE-2025-0503",
"products": [],
"severity": "low",
"structured": {
"id": "CVE-2025-0503",
"aliases": [
"CVE-2025-0503"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/mattermost/mattermost",
"type": "GIT",
"events": [
{
"introduced": "0bc2ddd42375a75ab14e63f038165150d4f07659"
},
{
"fixed": "6519009694d3a09586df7632261b441238d91f74"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "9.11.0"
},
{
"fixed": "9.11.7"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v9.11.7-rc2",
"v9.11.7-rc1",
"v9.11.6",
"v9.11.6-rc2",
"v9.11.6-rc1",
"v9.11.5",
"v9.11.5-rc1",
"v9.11.4",
"v9.11.4-rc1",
"v9.11.3",
"v9.11.3-rc2",
"v9.11.3-rc1",
"v9.11.2",
"v9.11.2-rc2",
"v9.11.2-rc1",
"v9.11.1-rc1",
"v9.11.1",
"v9.11.0-rc3",
"v9.11.0",
"@mattermost/types@9.11.0",
"@mattermost/client@9.11.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-0503.json"
}
}
],
"modified": "2026-10-28T02:30:50.354125331Z",
"provider": "osv",
"references": [
"https://mattermost.com/security-updates",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/0xxx/CVE-2025-0503.json",
"https://nvd.nist.gov/vuln/detail/CVE-2025-0503"
],
"provider_metadata": {
"cwe_ids": [
"CWE-754"
],
"cna_assigner": "Mattermost",
"unresolved_ranges": [
{
"extracted_events": [
{
"range": [
{
"introduced": "9.11.0"
},
{
"last_affected": "9.11.6"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
}
]
}
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/0xxx/CVE-2025-0503.json"
}
},
"related_cves": [
{
"value": "CVE-2025-0503",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 518990,
"published_at": "2025-02-14T17:52:17.895+00:00"
}