CVE-2023-38403 in iperf3
Summary
by MITRE • 07/18/2023
iperf3 before 3.14 allows peers to cause an integer overflow and heap corruption via a crafted length field.
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Analysis
by VulDB Data Team • 05/20/2025
The vulnerability identified as CVE-2023-38403 affects iperf3 versions prior to 3.14 and represents a critical security flaw that can be exploited to cause integer overflow and subsequent heap corruption within the network performance testing tool. This issue arises from insufficient validation of length fields in network packet processing, creating a pathway for remote attackers to manipulate the application's memory management. The vulnerability specifically targets the handling of crafted length fields that are processed during network data transmission and reception, where the application fails to properly validate the boundaries of integer values before performing memory allocation operations.
The technical implementation of this vulnerability stems from improper input validation mechanisms within the iperf3 protocol parsing logic. When processing network packets containing maliciously crafted length fields, the application performs arithmetic operations on these values without adequate overflow checking, leading to integer wraparound conditions. This integer overflow subsequently results in incorrect memory allocation calculations, causing heap corruption that can be leveraged for arbitrary code execution or denial of service conditions. The flaw aligns with CWE-190, which specifically addresses integer overflow conditions, and represents a classic example of improper integer handling in network protocol implementations.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it can be exploited to achieve remote code execution on systems running vulnerable versions of iperf3. Attackers can craft specially formatted network packets that trigger the integer overflow during packet processing, potentially allowing them to overwrite adjacent memory locations or manipulate heap metadata. This creates opportunities for privilege escalation, data corruption, or complete system compromise depending on the execution environment. The vulnerability affects systems that rely on iperf3 for network performance testing and monitoring, particularly in enterprise environments where network diagnostics and bandwidth testing are conducted regularly.
Security professionals should prioritize patching affected systems to address this vulnerability, as the potential for exploitation remains high given the nature of network performance testing tools that are commonly deployed in production environments. The recommended mitigation strategy involves upgrading to iperf3 version 3.14 or later, which includes proper input validation and integer overflow protection mechanisms. Additionally, network segmentation and monitoring should be implemented to detect anomalous packet patterns that might indicate exploitation attempts. Organizations should also consider implementing network access controls to limit exposure of iperf3 services to trusted networks only, aligning with ATT&CK technique T1071.004 for application layer protocol usage and T1210 for exploitation of remote services. The vulnerability demonstrates the importance of robust input validation in network applications and highlights the need for comprehensive security testing of protocol implementations to prevent similar issues in other network tools and services.