CVE-2025-9386 in tcpreplay
Summary
by MITRE • 08/24/2025
A vulnerability has been found in appneta tcpreplay up to 4.5.1. The impacted element is the function get_l2len_protocol of the file get.c of the component tcprewrite. Such manipulation leads to use after free. The attack must be carried out locally. The exploit has been disclosed to the public and may be used. Upgrading to version 4.5.2-beta3 is sufficient to resolve this issue. You should upgrade the affected component.
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Analysis
by VulDB Data Team • 10/07/2025
The vulnerability identified as CVE-2025-9386 represents a critical use after free condition within the appneta tcpreplay software suite, specifically affecting version 4.5.1 and earlier. This flaw exists in the get_l2len_protocol function located within the get.c file of the tcprewrite component, which is a core utility for replaying tcpdump files. The vulnerability arises from improper memory management where freed memory locations are accessed after the memory has been deallocated, creating a potential avenue for arbitrary code execution or system instability. The attack vector requires local system access, meaning an attacker must already have access to the target system to exploit this vulnerability, though the disclosed exploit demonstrates that such attacks are actively being used in the wild. This use after free condition stems from a fundamental flaw in how the application handles memory allocation and deallocation processes during packet processing operations, particularly when dealing with layer 2 protocol information extraction.
The operational impact of this vulnerability extends beyond simple memory corruption, as it can potentially allow attackers to execute malicious code with the privileges of the running process, which typically operates with elevated permissions due to the nature of packet manipulation tools. When exploited, this vulnerability could enable an attacker to gain unauthorized access to network monitoring systems, potentially leading to data exfiltration, network traffic manipulation, or complete system compromise. The tcpreplay suite is commonly used in network security testing, performance analysis, and traffic replay scenarios, making systems running vulnerable versions particularly attractive targets for attackers seeking to exploit network infrastructure tools. The vulnerability's classification aligns with CWE-416, which specifically addresses use after free conditions, and follows patterns commonly seen in memory safety issues that have been documented in the ATT&CK framework under privilege escalation and execution techniques.
Mitigation efforts should focus on immediate deployment of version 4.5.2-beta3 or later, which includes patches addressing the memory management flaw in the get_l2len_protocol function. Organizations should conduct thorough vulnerability assessments to identify all systems running affected versions of tcpreplay and prioritize remediation efforts accordingly. Additionally, system administrators should implement strict access controls to limit local system access, as the vulnerability requires local execution capabilities to be exploited. The patch addresses the root cause by implementing proper memory deallocation checks and ensuring that no references to freed memory locations persist after the memory has been released. Security teams should also consider monitoring for suspicious network activity that might indicate exploitation attempts, as use after free vulnerabilities often manifest through unusual system behavior or memory access patterns that can be detected through appropriate logging and monitoring configurations.