CVE-2021-38386 Explained : Impact and Mitigation

In Contiki 3.0, a buffer overflow in the Telnet service allows remote attackers to cause a denial of service because the ls command is mishandled when a directory has many files with long names.

Understanding CVE-2021-38386

This CVE describes a vulnerability in Contiki 3.0 that can be exploited by remote attackers to trigger a denial of service by exploiting the mishandling of the ls command.

What is CVE-2021-38386?

CVE-2021-38386 is a buffer overflow vulnerability in the Telnet service in Contiki 3.0 that can be abused by attackers to disrupt the service by manipulating directories with numerous files containing long names.

The Impact of CVE-2021-38386

The impact of this vulnerability is the potential for remote attackers to orchestrate denial-of-service attacks on systems running Contiki 3.0, leading to service disruption.

Technical Details of CVE-2021-38386

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability lies in the Telnet service of Contiki 3.0, where remote attackers can exploit a buffer overflow by manipulating directories with long-named files, triggering a denial of service.

Affected Systems and Versions

The buffer overflow issue affects Contiki 3.0, exposing systems running this version to potential denial-of-service attacks.

Exploitation Mechanism

Attackers exploit the mishandling of the ls command when directories contain many files with long names, triggering the buffer overflow and causing a denial of service.

Mitigation and Prevention

To safeguard systems from CVE-2021-38386, consider the following measures.

Immediate Steps to Take

Implement access controls, restrict Telnet service usage, and ensure directories do not contain an excessive number of files with long names.

Long-Term Security Practices

Regularly monitor and update directory structures, employ secure coding practices, and conduct security assessments to prevent buffer overflow vulnerabilities.

Patching and Updates

Apply security patches provided by Contiki to address the buffer overflow vulnerability in the Telnet service of Contiki 3.0.