Medium
Security advisory
Mattermost 6.2 and earlier fails to sufficiently process a specifically crafted GIF file when it is uploaded while drafting a post, which allows authenticated users to cause resource exhaustion while processing the file, resulting in server-side Denial of Service.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-37865
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 08:08 UTC · Revision 1
Source evidence
Mattermost 6.2 and earlier fails to sufficiently process a specifically crafted GIF file when it is uploaded while drafting a post, which allows authenticated users to cause resource exhaustion while processing the file, resulting in server-side Denial of Service.
osv:CVE-2021-37865
Complete source record
{
"id": "565e1ee74bda56df6c1edb7e080bba81c996166117097f3cc519d886b2b2a6ba",
"url": "https://osv.dev/vulnerability/CVE-2021-37865",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-37865",
"summary": "Mattermost 6.2 and earlier fails to sufficiently process a specifically crafted GIF file when it is uploaded while drafting a post, which allows authenticated users to cause resource exhaustion while processing the file, resulting in server-side Denial of Service.",
"evidence": "osv:CVE-2021-37865",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2021-37865",
"aliases": [
"CVE-2021-37865"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/mattermost/mattermost",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "7dcc03f1a215faaa5ded6592fb06420a8d87f439"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "6.2.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v6.2.0",
"cloud-2021-11-23-1",
"cloud-2021-11-11-1",
"cloud-2021-11-09-1",
"cloud-2021-10-27-1",
"cloud-2021-10-12-1",
"cloud-2021-09-29-1",
"cloud-2021-08-12-1",
"cloud-2021-07-29-1",
"cloud-2021-07-15-1",
"cloud-2021-07-01-1",
"cloud-2021-06-16-1",
"cloud-2021-06-02-1",
"cloud-2021-05-21-1",
"cloud-2021-05-05-1",
"cloud-2021-04-22-1",
"cloud-2021-03-23-1",
"cloud-2021-03-12-1",
"cloud-2021-02-25-1",
"cloud-2021-02-24",
"cloud-2021-02-10",
"cloud-2021-01-26",
"cloud-2021-01-12",
"cloud-2020-12-18",
"cloud-2020-12-08",
"cloud-2020-11-24",
"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-2021-37865.json"
}
}
],
"modified": "2026-10-24T10:31:03.508237200Z",
"provider": "osv",
"references": [
"https://mattermost.com/security-updates/",
"https://hackerone.com/reports/1428260"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-37865",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 440272,
"published_at": "2022-01-18T17:15:08.457+00:00"
}