CVE-2023-38403

An integer overflow flaw was found in the way iperf3 dynamically allocates memory buffers for JSON-formatted messages. A remote attacker could send a specially crafted sequence of bytes on the iperf3 control channel with a specified JSON message length of 0xffffffff to trigger an integer overflow leading the receiving process to abort due to heap corruption. This flaw allows an attacker to use a malicious client to cause a denial of service of an iperf3 server or potentially use a malicious server to cause connecting clients to crash.

Mitigation

Do not run iperf3 as a publicly accessible service unless required. If required, restrict availability to the iperf3 server to only allow access from network ranges of trusted clients. Do not connect to iperf3 servers that you do not trust.