Critical
Security advisory
In versions prior to 1.1 of the Eclipse Paho MQTT C Client, the client does not check rem_len size in readpacket.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-41036
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 11:55 UTC · Revision 1
Source evidence
In versions prior to 1.1 of the Eclipse Paho MQTT C Client, the client does not check rem_len size in readpacket.
osv:CVE-2021-41036
Complete source record
{
"id": "58e026d275a5227b9c01799b56d477ee41f5d686aafefdd6bfba61cbce0a83c7",
"url": "https://osv.dev/vulnerability/CVE-2021-41036",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-41036",
"summary": "In versions prior to 1.1 of the Eclipse Paho MQTT C Client, the client does not check rem_len size in readpacket.",
"evidence": "osv:CVE-2021-41036",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2021-41036",
"aliases": [
"CVE-2021-41036"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/eclipse-paho/paho.mqtt.embedded-c",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "1e7c3371142985a282bc1089ce4385297eb53640"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:eclipse:paho_mqtt_c\\/c\\+\\+_client:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "1.1.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v1.0.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-41036.json"
}
}
],
"modified": "2026-10-20T10:54:57.470942336Z",
"provider": "osv",
"references": [
"https://github.com/eclipse/paho.mqtt.embedded-c/issues/96"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-41036",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 386540,
"published_at": "2021-11-03T00:15:08.023+00:00"
}