CVE-2026-101283 PUBLISHED

Assigner: Anthropic
Reserved: 28.09.2026 Published: 30.09.2026 Updated: 01.10.2026

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

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 9.2

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	Present	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	esnet
Product	iperf3
Versions	Default: unaffected Version 3.20 is affected Version 3.21 is affected

Credits

Anthropic finder
Ada Logics analyst

References

https://newreleases.io/project/github/esnet/iperf/release/3.22

Problem Types

CWE-122 Heap-based buffer overflow CWE

Impacts

CAPEC-100 Overflow Buffers