CVE-2023-0666: Wireshark Buffer Overflow Vulnerability

CVE-2023-0666 Overview

CVE-2023-0666 is a heap-based buffer overflow vulnerability affecting Wireshark, the widely-used network protocol analyzer. The vulnerability exists in the RTPS (Real-Time Publish-Subscribe) protocol dissector, where improper validation of packet length fields allows attackers to craft malicious RTPS packets that trigger memory corruption. Successful exploitation could result in denial of service through application crash or potentially arbitrary code execution within the context of the Wireshark process.

Critical Impact

Organizations using vulnerable Wireshark versions to analyze network traffic containing malicious RTPS packets may experience application crashes or potential compromise of analyst workstations.

Affected Products

• Wireshark version 4.0.5 and prior
• Wireshark version 3.6.x series (prior to fix)
• Debian Linux 12.0

Discovery Timeline

• 2023-06-07 - CVE-2023-0666 published to NVD
• 2025-11-03 - Last updated in NVD database

Technical Details for CVE-2023-0666

Vulnerability Analysis

This vulnerability is classified as CWE-122 (Heap-based Buffer Overflow) and CWE-787 (Out-of-bounds Write). The flaw resides in the RTPS protocol dissector component of Wireshark, which is responsible for parsing Real-Time Publish-Subscribe protocol packets commonly used in DDS (Data Distribution Service) implementations.

The vulnerability allows a remote attacker to cause a heap-based buffer overflow by sending specially crafted RTPS packets to a system where Wireshark is capturing and analyzing network traffic. The dissector fails to properly validate length fields within RTPS packets before using them in memory operations, enabling an attacker to overflow heap-allocated buffers.

While the primary impact is denial of service through application crash, the nature of heap-based buffer overflows means that with sufficient exploitation sophistication, arbitrary code execution may be achievable in the context of the Wireshark process.

Root Cause

The root cause is insufficient input validation in the RTPS dissector code. Specifically, when processing RTPS packets, the dissector uses attacker-controlled length values without proper bounds checking. This allows an attacker to specify a length value that exceeds the actual allocated buffer size, resulting in out-of-bounds memory writes.

The RTPS dissector trusts packet-supplied length fields when copying data into memory buffers, violating secure coding principles that require validation of all external input before use in memory operations.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker must craft a malicious RTPS packet and ensure it is captured by a vulnerable Wireshark instance. This can occur in several scenarios:

The victim opens a malicious packet capture file (PCAP) containing the crafted RTPS packet. Alternatively, the victim actively captures network traffic on a network where the attacker can inject malicious RTPS packets. The attacker sends specially crafted RTPS packets that, when parsed by Wireshark's RTPS dissector, trigger the heap overflow condition due to the invalid length value being processed without proper validation.

Detection Methods for CVE-2023-0666

Indicators of Compromise

• Wireshark application crashes when analyzing RTPS protocol traffic
• Unexpected termination of tshark or wireshark processes during packet analysis
• Core dumps or crash logs indicating heap corruption in RTPS dissector functions
• Anomalous RTPS packets with irregular length field values in captured traffic

Detection Strategies

• Monitor for Wireshark process crashes and analyze crash dumps for RTPS dissector involvement
• Implement network monitoring to detect malformed RTPS packets with suspicious length fields
• Deploy endpoint detection solutions to identify exploitation attempts targeting analysis tools
• Use SentinelOne to detect memory corruption attacks and anomalous process behavior

Monitoring Recommendations

• Enable crash reporting and logging for Wireshark installations across the organization
• Monitor system logs for repeated Wireshark crashes that may indicate exploitation attempts
• Track versions of Wireshark deployed across endpoints and flag vulnerable installations
• Review packet capture files from untrusted sources in isolated environments

How to Mitigate CVE-2023-0666

Immediate Actions Required

• Upgrade Wireshark to version 4.0.6 or later immediately
• For version 3.6.x, upgrade to 3.6.14 or later
• Avoid opening packet capture files from untrusted sources on vulnerable systems
• Disable the RTPS dissector if RTPS protocol analysis is not required

Patch Information

Wireshark has released version 4.0.6 which addresses this vulnerability. The fix implements proper bounds checking for length fields in the RTPS dissector before memory operations are performed. Detailed information is available in the Wireshark Security Advisory wnpa-sec-2023-18 and the Wireshark Release Notes 4.0.6.

Debian users should apply the patches provided in Debian DSA-5429. Gentoo users can refer to GLSA 202309-02 for distribution-specific guidance.

Workarounds

• Disable the RTPS protocol dissector via Edit → Preferences → Protocols → RTPS → Uncheck "Decode RTPS"
• Analyze suspicious packet captures in isolated virtual machines
• Use the command-line option --disable-protocol rtps when running tshark for batch analysis
• Implement network segmentation to limit exposure of analysis workstations

# Disable RTPS dissector via command line
tshark --disable-protocol rtps -r suspicious_capture.pcap

# Alternatively, create a disabled protocols file
echo "rtps" >> ~/.config/wireshark/disabled_protos