CVE-2026-10143

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/dpkp/kafka-python/commit/6e4831444f972d169cdd11f5c8d50333cea3f19b	Patch
https://github.com/dpkp/kafka-python/pull/3019	Issue Tracking Patch
https://github.com/dpkp/kafka-python/pull/3026	Issue Tracking Patch
https://www.vulncheck.com/advisories/kafka-python-prior-to-dos-via-scram-iteration-count-in-scram-py	Patch Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:28571
https://access.redhat.com/errata/RHSA-2026:30076
https://access.redhat.com/errata/RHSA-2026:33683
https://access.redhat.com/errata/RHSA-2026:41066
https://access.redhat.com/errata/RHSA-2026:42796
https://access.redhat.com/security/cve/CVE-2026-10143
https://bugzilla.redhat.com/show_bug.cgi?id=2487722
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-10143.json

Configurations

Configuration 1 (hide)

cpe:2.3:a:dpkp:kafka-python:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-06-10 22:16

Updated : 2026-09-10 13:17

NVD link : CVE-2026-10143

Mitre link : CVE-2026-10143

CVE.ORG link : CVE-2026-10143

JSON object : View

Products Affected

dpkp

kafka-python

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-606

Unchecked Input for Loop Condition

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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."}, {"lang": "es", "value": "kafka-python anterior a 2.3.2 contiene una vulnerabilidad de denegaci\u00f3n de servicio en el manejo de la autenticaci\u00f3n SCRAM que permite a un br\u00f3ker malicioso o de m\u00e1quina-en-el-medio congelar el bucle de eventos del cliente al proporcionar un recuento de iteraciones excesivamente grande. En scram.py, ScramClient.process_server_first_message() pasa el recuento de iteraciones SCRAM controlado por el br\u00f3ker directamente a hashlib.pbkdf2_hmac() sin validaci\u00f3n, bloqueando los env\u00edos del productor, las encuestas del consumidor, las operaciones de administraci\u00f3n y los latidos, lo que puede causar la expulsi\u00f3n del grupo de consumidores y fallos repetidos de reconexi\u00f3n."}], "lastModified": "2026-09-10T13:17:30.657", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:dpkp:kafka-python:*:*:*:*:*:python:*:*", "vulnerable": true, "matchCriteriaId": "6E5BAD52-2501-4C08-AFC6-8958B4974860", "versionEndExcluding": "2.3.2"}], "operator": "OR"}]}], "sourceIdentifier": "disclosure@vulncheck.com"}