Use After Free in Esnet Iperf3

CVE-2026-101276

iperf3 3.21 (esnet/iperf) contains a remote, unauthenticated heap use-after-free: the server's per-test watchdog server_timer_proc() frees streams without cancelling/joining their worker threads, so a blocked worker dereferences a freed iperf_stream; fixed in 3.22.

Vulnerability class: Use-After-Free

Published · last modified .

EPSS exploit prediction

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Affected products

Weakness classification (CWE)

References