CVE-2021-39920 : What You Need to Know

A NULL pointer exception in the IPPUSB dissector in Wireshark 3.4.0 to 3.4.9 could allow denial of service through packet injection or a crafted capture file.

Understanding CVE-2021-39920

Wireshark vulnerability impacting versions 3.4.0 to 3.4.9 allowing denial of service attacks.

What is CVE-2021-39920?

The CVE-2021-39920 vulnerability involves a NULL pointer exception in the IPPUSB dissector in Wireshark versions 3.4.0 to 3.4.9. Attackers could exploit this issue to cause denial of service via packet injection or a malicious capture file.

The Impact of CVE-2021-39920

The vulnerability could result in denial of service attacks on systems running affected versions of Wireshark (3.4.0 to 3.4.9) through the exploitation of a NULL pointer exception in the IPPUSB dissector.

Technical Details of CVE-2021-39920

Details on the vulnerability affecting Wireshark versions 3.4.0 to 3.4.9.

Vulnerability Description

Type: Null pointer dereference in Wireshark

Affected Systems and Versions

Vendor: Wireshark Foundation
Product: Wireshark
Affected Versions: >=3.4.0, <3.4.10

Exploitation Mechanism

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Impact: High availability impact with a base score of 7.5 (High severity)

Mitigation and Prevention

Steps to mitigate and prevent exploitation of CVE-2021-39920.

Immediate Steps to Take

Upgrade Wireshark to version 3.4.10 or newer to prevent exploitation.
Avoid opening suspicious or untrusted capture files.

Long-Term Security Practices

Regularly update and patch Wireshark to the latest version.
Implement network security measures to detect and prevent denial of service attacks.

Patching and Updates

Stay informed about security advisories from Wireshark Foundation and apply patches promptly.