CVE-2026-10143
HIGH 8.7kafka-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.
Severe if exploited (CVSS 8.7), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.5%chance of exploitation in 30 days · 39th percentile
Impact if exploited
8.7CVSS 4.0 · HIGH
- ConfidentialityNone
- IntegrityNone
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
- ✓Requirements: No special attack requirements
✓ lowers the bar for an attacker · ⚠ raises it
Affected
Vendors Dana Powers Red Hat
Products Kafka Python Red Hat Quay 3.10 Red Hat Quay 3.12 Red Hat Quay 3.9 Red Hat Quay 3
Weakness (CWE)
- CWE-400: Uncontrolled resource consumption
- CWE-606
CVSS vector
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