Buffer overflow in Esnet Iperf3

CVE-2026-101283

iperf3 3.20–3.21 (esnet/iperf) has a pre-auth heap buffer overflow in decrypt_rsa_message(): a 256-byte RSA buffer is BIO_read with the attacker-controlled ciphertext length (guard warns only), so an unauthenticated client overflows the heap via an oversized authtoken; fixed in 3.22

Vulnerability class: Buffer Overflow

Published · last modified .

EPSS exploit prediction

EPSS: 0.004 (34.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 35th percentile — 34.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Weakness classification (CWE)

References