CVE-2026-10143 (GCVE-0-2026-10143)

Vulnerability from cvelistv5 – Published: 2026-06-10 20:22 – Updated: 2026-06-10 20:22
VLAI
Title
kafka-python prior to 2.3.2 DoS via SCRAM Iteration Count in scram.py
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7 (High)
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
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version
Dana Powers kafka-python Affected: 0 , < 2.3.2 (git)
Create a notification for this product.
Date Public
2026-06-10 20:00
Credits
Katriel Moses
Show details on NVD website
To clipboard 

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}


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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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