Critical Wireshark Vulnerability

Summary

Security researchers have disclosed a large-scale vulnerability update affecting the Wireshark network protocol analyzer, where over 40 security flaws were patched some enabling arbitrary code execution (RCE) via malformed packets or malicious capture files.

The vulnerabilities:
• Affect enterprise and SOC environments using Wireshark
• Include multiple remote code execution risks
• Impact over 20 protocol dissectors and core decoding engines
• Require only network traffic or malicious capture files to trigger

Research Source

The vulnerabilities were reported and analyzed by cybersecurity researchers and confirmed in the official Wireshark security advisory for version 4.6.5.

Key affected components include:
• TLS, RDP, SBC, and Profile Import modules
• SMB2, OpenFlow, and MBIM protocol dissectors
• zlib and LZ77 decompression engines

The findings highlight increasing use of AI-assisted vulnerability discovery, which helped identify multiple flaws across protocol layers simultaneously.

Technical Details

The issues stem from parsing and memory-handling flaws within Wireshark’s protocol dissectors and decoding engines.

Critical Code Execution Vulnerabilities

Several high-severity bugs allow potential remote code execution:

• TLS Dissector (CVE-2026-5402) — malformed TLS traffic crash with possible RCE
• SBC Codec (CVE-2026-5403) — audio codec memory corruption
• RDP Dissector (CVE-2026-5405) — malformed RDP packet execution risk
• Profile Import (CVE-2026-5656) — malicious capture file execution path

Denial-of-Service (DoS) Vulnerabilities

More than 20 dissectors are affected by crash or memory exhaustion issues:

Examples include:
• ICMPv6, HTTP, MySQL, WebSocket
• ZigBee, Kismet, RTSP, IEEE 802.11
• GSM RP, AFP, AMR-NB, DCP-ETSI

Attackers can trigger crashes using crafted network packets, requiring no authentication.

Infinite Loop Vulnerabilities

Some flaws cause Wireshark to hang indefinitely, including:

• SMB2 Dissector (CVE-2026-5407)
• OpenFlow and MBIM protocols
• USB HID and DLMS/COSEM modules

These can disrupt live packet capture and SIEM pipelines, potentially halting analysis systems.

Decompression Engine Flaws

Core parsing engines are also affected:

• zlib decompression crash (CVE-2026-6535)
• LZ77 decompression crash (CVE-2026-6533)

These issues expand attack surface across any compressed network traffic.

Observed Attack Scenario
Initial Access

• Attacker must be on same network segment OR
• Deliver malicious capture file to analyst/SOC system

Execution

• Crafted packet stream or capture file processed by Wireshark
• Trigger memory corruption or logic failure in dissector

Impact

• Arbitrary code execution (in severe cases)
• Application crash or system freeze
• Potential privilege escalation in elevated SOC environments

Persistence

• No persistence required (stateless packet-based attacks)
• Repeatable via network traffic injection

Threat Actor

Attribution:
• No specific threat actor identified
• Likely to be exploited by:

Network-based attackers
Advanced persistent threat groups
Internal malicious actors in enterprise networks

Given Wireshark’s usage in SOC environments, exploitation could be highly valuable for network visibility disruption or lateral reconnaissance evasion.

Impact

This vulnerability set introduces significant operational risk:

• Remote code execution in enterprise monitoring tools
• Disruption of SOC and forensic workflows
• Denial-of-service via traffic-based crashes
• Potential blind spots in network visibility during attacks

For organizations:
• Risk of compromised analysis systems
• Interruption of incident response operations
• Reduced ability to detect active intrusions

Mitigation

Recommended actions:

Immediate upgrade:
• Update to Wireshark 4.6.5 or later

Operational controls:
• Restrict Wireshark usage to trusted environments
• Avoid running packet capture tools with elevated privileges unnecessarily
• Limit exposure of capture interfaces on untrusted networks

Security monitoring:
• Watch for malformed packet floods
• Monitor unexpected crashes in network analysis tools
• Validate capture file sources before analysis

References
• https://cybersecuritynews.com/wireshark-vulnerabilities-code-execution/