CVE-2023-39946 Explained : Impact and Mitigation

A heap overflow vulnerability in eProsima Fast DDS allows remote attackers to crash Fast-DDS processes by triggering a buffer overflow in

eprosima::fastdds::dds::ParameterPropertyList_t::push_back_helper

function.

Understanding CVE-2023-39946

This CVE involves a heap-based buffer overflow vulnerability in eProsima Fast DDS, impacting versions prior to 2.11.1, 2.10.2, 2.9.2, and 2.6.6.

What is CVE-2023-39946?

Before versions 2.11.1, 2.10.2, 2.9.2, and 2.6.6, eProsima Fast DDS is susceptible to a heap overflow triggered by a specific CDR message.

The Impact of CVE-2023-39946

The vulnerability allows remote attackers to crash Fast-DDS processes by sending a crafted CDR message to the discovery port, leading to a denial of service condition.

Technical Details of CVE-2023-39946

This section covers the specifics of the vulnerability.

Vulnerability Description

By manipulating the PID_PROPERTY_LIST parameter and sending a CDR string with excessive length, attackers can overflow the heap in

push_back_helper

function due to the inadequate handling of data.

Affected Systems and Versions

Vendor: eProsima
Product: Fast-DDS
Affected Versions:
< 2.6.6

= 2.7.0, < 2.9.2

= 2.10.0, < 2.10.2

= 2.11.0

Exploitation Mechanism

Attackers can exploit this vulnerability by sending a malicious CDR string to the discovery multicast port, manipulating the size and data copied by

memcpy

, ultimately leading to a crash.

Mitigation and Prevention

Below are the crucial steps to mitigate and prevent exploitation of CVE-2023-39946.

Immediate Steps to Take

Users are advised to update to the patched versions (2.11.1, 2.10.2, 2.9.2, or 2.6.6) to eliminate the vulnerability and prevent potential crashes.

Long-Term Security Practices

Implement robust input validation mechanisms, sanitize user inputs, and regularly update software to prevent buffer overflows and remote attacks.

Patching and Updates

Regularly check for security advisories and updates from eProsima, ensuring timely application of patches to secure Fast-DDS installations.