CVE-2020-15475 in nDPI
Summary
by MITRE
In nDPI through 3.2, ndpi_reset_packet_line_info in lib/ndpi_main.c omits certain reinitialization, leading to a use-after-free.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 07/02/2020
The vulnerability identified as CVE-2020-15475 affects the nDPI network protocol detection library version 3.2 and earlier, representing a critical memory safety issue that can lead to arbitrary code execution. This flaw exists within the ndpi_reset_packet_line_info function located in the lib/ndpi_main.c source file, where the function fails to properly reinitialize certain internal data structures during packet processing cycles. The incomplete reinitialization creates a scenario where previously freed memory locations may still be referenced, establishing a use-after-free condition that can be exploited by malicious actors to execute arbitrary code or cause denial of service.
The technical implementation of this vulnerability stems from improper memory management practices within the nDPI library's packet processing pipeline. When the ndpi_reset_packet_line_info function is called to reset packet information for subsequent processing, it neglects to properly reset specific internal pointers and state variables that track packet line information. This oversight allows attackers to craft specially malformed network packets that, when processed by the vulnerable library, can trigger the use-after-free condition. The flaw is particularly dangerous because it occurs during normal packet processing operations, making it difficult to detect and exploit through conventional means.
The operational impact of CVE-2020-15475 extends beyond simple denial of service scenarios to encompass potential remote code execution capabilities. Systems utilizing vulnerable nDPI versions in network monitoring, intrusion detection, or traffic analysis applications become susceptible to exploitation, as these systems process large volumes of network traffic through the affected library. The vulnerability affects network security appliances, firewalls, network monitoring tools, and any application that relies on nDPI for protocol identification and classification. Attackers can leverage this weakness to gain unauthorized access to systems, escalate privileges, or disrupt network services, making it a significant concern for enterprise security infrastructures.
Security mitigations for this vulnerability require immediate patching of affected nDPI library versions to the latest releases that contain proper memory reinitialization logic. Organizations should implement comprehensive network monitoring to detect exploitation attempts and deploy intrusion detection systems that can identify malformed packets designed to trigger the use-after-free condition. Additionally, network segmentation and access controls should be strengthened to limit potential attack surface exposure. The vulnerability aligns with CWE-416, which categorizes use-after-free conditions as memory safety issues, and represents a technique that could be mapped to ATT&CK tactic TA0001 (Initial Access) through network-based attack vectors or TA0005 (Defense Evasion) when used to maintain persistence. System administrators must also consider implementing network traffic filtering rules that can identify and block suspicious packet patterns associated with exploitation attempts, while conducting thorough vulnerability assessments to ensure all network infrastructure components are properly updated and patched.