Critical
paho.mqtt.c — 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
- paho.mqtt.c
- Affected versions
- 1.3.12-1, 1.3.13-1, 1.3.13-1build1, 1.3.13-1build2, 1.3.14-2, 1.3.15-1, 1.3.16+ds-1, 1.3.16+ds-1build1, 1.3.9-1, 1.3.9-1build1
- Fixed versions
- Not specified
- CVEs
- CVE-2021-41036
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 01:00 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:UBUNTU-CVE-2021-41036
paho.mqtt.c
Fixed versions: Not specified
paho.mqtt.c
Fixed versions: Not specified
paho.mqtt.c
Fixed versions: Not specified
paho.mqtt.c
Fixed versions: Not specified
paho.mqtt.c
Fixed versions: Not specified
Complete source record
{
"id": "b140f14ba2301e382f4b5b4ac6ff2cb265279305b05e88c9dfd4f73fbb4c873f",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2021-41036",
"method": "structured",
"payload": {
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"title": "UBUNTU-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:UBUNTU-CVE-2021-41036",
"products": [
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"aliases": [
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"metrics": [
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"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
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{
"type": "Ubuntu",
"score": "medium"
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"affected": [
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"versions": [
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"database_specific": {
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},
"ecosystem_specific": {
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{
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"package": {
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"purl": "pkg:deb/ubuntu/paho.mqtt.c?arch=source&distro=noble",
"ecosystem": "Ubuntu:24.04:LTS"
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"versions": [
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},
"versions": [
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"purl": "pkg:deb/ubuntu/paho.mqtt.c?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
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"versions": [
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"1.3.16+ds-1",
"1.3.16+ds-1build1"
],
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},
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{
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"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
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],
"database_specific": {
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},
"ecosystem_specific": {
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{
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},
{
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}
],
"modified": "2026-10-17T12:56:20.797244044Z",
"provider": "osv",
"upstream": [
"CVE-2021-41036"
],
"references": [
"https://ubuntu.com/security/CVE-2021-41036",
"https://github.com/eclipse/paho.mqtt.embedded-c/issues/96",
"https://www.cve.org/CVERecord?id=CVE-2021-41036"
]
},
"related_cves": [
{
"value": "CVE-2021-41036",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 355358,
"published_at": "2021-11-03T00:15:00+00:00"
}