HighFix available
python-kafka — security advisory
kafka-python prior to 2.3.2 contains a denial-of-service vulnerability in SCRAM authentication handling that allows a malicious or machine-in-the-middle broker to freeze the client event loop by supplying an excessively large iteration count. In scram.py, ScramClient.process_server_first_message() passes the broker-controlled SCRAM iteration count directly to hashlib.pbkdf2_hmac() without validation, blocking producer sends, consumer polls, admin operations, and heartbeats, which can cause consumer group eviction and repeated reconnect failures.
- Products
- python-kafka
- Affected versions
- 2.0.2-10, 2.0.2-11, 2.0.2-12, 2.0.2-13, 2.0.2-3, 2.0.2-4, 2.0.2-5, 2.0.2-6, 2.0.2-7, 2.0.2-8, 2.0.2-9, 2.2.3-1
- Fixed versions
- 2.0.2-12
- CVEs
- CVE-2026-10143
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 28 Oct 2026, 11:09 UTC · Revision 1
Source evidence
kafka-python prior to 2.3.2 contains a denial-of-service vulnerability in SCRAM authentication handling that allows a malicious or machine-in-the-middle broker to freeze the client event loop by supplying an excessively large iteration count. In scram.py, ScramClient.process_server_first_message() passes the broker-controlled SCRAM iteration count directly to hashlib.pbkdf2_hmac() without validation, blocking producer sends, consumer polls, admin operations, and heartbeats, which can cause consumer group eviction and repeated reconnect failures.
osv:DEBIAN-CVE-2026-10143
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: 2.0.2-12
Complete source record
{
"id": "10d802d28f8fa095cf83d5971f7eddf9e0e7cae42f4066d8db4ebb8950bba342",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-10143",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-10143",
"summary": "kafka-python prior to 2.3.2 contains a denial-of-service vulnerability in SCRAM authentication handling that allows a malicious or machine-in-the-middle broker to freeze the client event loop by supplying an excessively large iteration count. In scram.py, ScramClient.process_server_first_message() passes the broker-controlled SCRAM iteration count directly to hashlib.pbkdf2_hmac() without validation, blocking producer sends, consumer polls, admin operations, and heartbeats, which can cause consumer group eviction and repeated reconnect failures.",
"evidence": "osv:DEBIAN-CVE-2026-10143",
"products": [
{
"name": {
"value": "python-kafka",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.0.2-10",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-11",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-12",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-13",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-3",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-4",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-5",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-6",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-7",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-8",
"evidence": "/affected/0/versions"
},
{
"value": "2.0.2-9",
"evidence": "/affected/0/versions"
},
{
"value": "2.2.3-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "python-kafka",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.0.2-10",
"evidence": "/affected/1/versions"
},
{
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"evidence": "/affected/1/versions"
},
{
"value": "2.0.2-12",
"evidence": "/affected/1/versions"
},
{
"value": "2.0.2-13",
"evidence": "/affected/1/versions"
},
{
"value": "2.0.2-9",
"evidence": "/affected/1/versions"
},
{
"value": "2.2.3-1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "python-kafka",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.0.2-12",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "2.0.2-10",
"evidence": "/affected/2/versions"
},
{
"value": "2.0.2-11",
"evidence": "/affected/2/versions"
},
{
"value": "2.0.2-9",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-10143",
"aliases": [
"DEBIAN-CVE-2026-10143"
],
"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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "python-kafka",
"purl": "pkg:deb/debian/python-kafka?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"2.0.2-10",
"2.0.2-11",
"2.0.2-12",
"2.0.2-13",
"2.0.2-3",
"2.0.2-4",
"2.0.2-5",
"2.0.2-6",
"2.0.2-7",
"2.0.2-8",
"2.0.2-9",
"2.2.3-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-10143.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "python-kafka",
"purl": "pkg:deb/debian/python-kafka?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"2.0.2-10",
"2.0.2-11",
"2.0.2-12",
"2.0.2-13",
"2.0.2-9",
"2.2.3-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-10143.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.0.2-12"
}
]
}
],
"package": {
"name": "python-kafka",
"purl": "pkg:deb/debian/python-kafka?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.0.2-10",
"2.0.2-11",
"2.0.2-9"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-10143.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-09T10:01:06.926006708Z",
"provider": "osv",
"upstream": [
"CVE-2026-10143"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-10143"
]
},
"related_cves": [
{
"value": "CVE-2026-10143",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 111743,
"published_at": "2026-06-10T22:16:55.503+00:00"
}