High
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
- 0.9.3-2, 1.3.2-0ubuntu1, 1.4.3-1, 1.4.6-1, 2.0.1-2, 2.0.2-10, 2.0.2-11, 2.0.2-12, 2.0.2-2, 2.0.2-4, 2.0.2-5, 2.0.2-9
- Fixed versions
- Not specified
- CVEs
- CVE-2026-10143
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 01:57 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:UBUNTU-CVE-2026-10143
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
python-kafka
Fixed versions: Not specified
Complete source record
{
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"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-10143",
"method": "structured",
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"modified": "2026-10-17T12:57:55.066763581Z",
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"references": [
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