CVE-2026-71218

A flaw was found in iperf3. A remote unauthenticated attacker can exploit a vulnerability in the JSON_read() function, which accepts a peer-controlled message length and allocates memory without an upper bound. This allows the attacker to trigger excessive memory consumption, leading to a Denial of Service (DoS) through memory exhaustion, severe slowdown, or termination of the iperf3 service.

A flaw was found in iperf3. A remote unauthenticated attacker can exploit a vulnerability in the JSON_read() function, which accepts a peer-controlled message length and allocates memory without an upper bound. This allows the attacker to trigger excessive memory consumption, leading to a Denial of Service (DoS) through memory exhaustion, severe slowdown, or termination of the iperf3 service.

A flaw was found in iperf3. A remote unauthenticated attacker can exploit a vulnerability in the JSON_read() function, which accepts a peer-controlled message length and allocates memory without an upper bound. This allows the attacker to trigger excessive memory consumption, leading to a Denial of Service (DoS) through memory exhaustion, severe slowdown, or termination of the iperf3 service.

Iperf3 server accepts unbounded peer-controlled json parameters enabling remote denial of service via resource exhaustion. (CVE-2026-71217) Unbounded peer-controlled allocation in iperf3 json_read() allows unauthenticated remote memory exhaustion. (CVE-2026-71218) 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. (CVE-2026-101276) 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. (CVE-2026-101283) Iperf3 < 3.22 UDP Receive Worker Infinite Loop DoS. (CVE-2026-102253)

These are all security issues fixed in the iperf-3.22-1.1 package on the GA media of openSUSE Tumbleweed.

This update for iperf fixes the following issues:

• CVE-2026-71217: iperf3 server accepts unbounded peer-controlled JSON parameters enabling remote denial of service via resource exhaustion (bsc#1284405).
• CVE-2026-71218: unbounded peer-controlled allocation in JSON_read() allows unauthenticated remote memory exhaustion (bsc#1284404).
• 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 (bsc#1283786).
• 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 (bsc#1283787).
• CVE-2026-102253: missing checks in the server's UDP receive worker allows unauthenticated remote attackers to cause an infinite loop (bsc#1283528).

Changes for iperf:

• Updated to version 3.22

This update for iperf fixes the following issues:

• CVE-2026-71217: iperf3 server accepts unbounded peer-controlled JSON parameters enabling remote denial of service via resource exhaustion (bsc#1284405).
• CVE-2026-71218: unbounded peer-controlled allocation in JSON_read() allows unauthenticated remote memory exhaustion (bsc#1284404).
• 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 (bsc#1283786).
• 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 (bsc#1283787).
• CVE-2026-102253: missing checks in the server's UDP receive worker allows unauthenticated remote attackers to cause an infinite loop (bsc#1283528).

Changes for iperf:

• Updated to version 3.22

This update for iperf fixes the following issues:

• CVE-2026-71217: iperf3 server accepts unbounded peer-controlled JSON parameters enabling remote denial of service via resource exhaustion (bsc#1284405).
• CVE-2026-71218: unbounded peer-controlled allocation in JSON_read() allows unauthenticated remote memory exhaustion (bsc#1284404).
• 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 (bsc#1283786).
• 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 (bsc#1283787).
• CVE-2026-102253: missing checks in the server's UDP receive worker allows unauthenticated remote attackers to cause an infinite loop (bsc#1283528).

Changes for iperf:

• Updated to version 3.22

This update for iperf fixes the following issues:

• CVE-2026-71217: iperf3 server accepts unbounded peer-controlled JSON parameters enabling remote denial of service via resource exhaustion (bsc#1284405).
• CVE-2026-71218: unbounded peer-controlled allocation in JSON_read() allows unauthenticated remote memory exhaustion (bsc#1284404).
• 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 (bsc#1283786).
• 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 (bsc#1283787).
• CVE-2026-102253: missing checks in the server's UDP receive worker allows unauthenticated remote attackers to cause an infinite loop (bsc#1283528).

Changes for iperf:

• Updated to version 3.22.