Medium
Fleet vulnerable to Denial of Service via unhandled gRPC log type in launcher endpoint
Type: advisorySources: OSV
Fleet is open source device management software. Prior to 4.81.0, a denial-of-service vulnerability in Fleet's gRPC Launcher endpoint allows an authenticated host to crash the entire Fleet server process by sending an unexpected log type value. The server terminates immediately, disrupting all connected hosts, MDM enrollments, and API consumers. Version 4.81.0 patches the issue.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-34388
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 17:23 UTC · Revision 1
Source evidence
Fleet vulnerable to Denial of Service via unhandled gRPC log type in launcher endpoint
core-osv · Original sourcePublished 27 Mar 2026, 19:13 UTC
Fleet is open source device management software. Prior to 4.81.0, a denial-of-service vulnerability in Fleet's gRPC Launcher endpoint allows an authenticated host to crash the entire Fleet server process by sending an unexpected log type value. The server terminates immediately, disrupting all connected hosts, MDM enrollments, and API consumers. Version 4.81.0 patches the issue.
osv:CVE-2026-34388
Complete source record
{
"id": "c413241d67dbcedf60cee16c73b47b0d605395026ce130116539a1236df58a6c",
"url": "https://osv.dev/vulnerability/CVE-2026-34388",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Fleet vulnerable to Denial of Service via unhandled gRPC log type in launcher endpoint",
"summary": "Fleet is open source device management software. Prior to 4.81.0, a denial-of-service vulnerability in Fleet's gRPC Launcher endpoint allows an authenticated host to crash the entire Fleet server process by sending an unexpected log type value. The server terminates immediately, disrupting all connected hosts, MDM enrollments, and API consumers. Version 4.81.0 patches the issue.",
"evidence": "osv:CVE-2026-34388",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-34388",
"aliases": [
"CVE-2026-34388",
"GHSA-w254-4hp5-7cvv",
"GO-2026-4915"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/fleetdm/fleet",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "9dbcc38ce1046074ac230804f32ae1689026041f"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "4.81.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"cpe": "cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "4.81.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
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],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-34388.json"
}
}
],
"modified": "2026-10-28T02:30:37.686539279Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34388.json",
"https://github.com/fleetdm/fleet/security/advisories/GHSA-w254-4hp5-7cvv",
"https://nvd.nist.gov/vuln/detail/CVE-2026-34388"
],
"provider_metadata": {
"cwe_ids": [
"CWE-703"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34388.json"
}
},
"related_cves": [
{
"value": "CVE-2026-34388",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 505294,
"published_at": "2026-03-27T19:13:00.388+00:00"
}