CVE-2021-20988 : Security Advisory and Response

In Hilscher rcX RTOS versions prior to V2.1.14.1, the actual UDP packet length is not verified against the length indicated by the packet, potentially leading to a denial of service for the affected device.

Understanding CVE-2021-20988

This CVE describes the vulnerability in Hilscher rcX RTOS due to incorrect handling of the UDP checksum.

What is CVE-2021-20988?

The vulnerability in Hilscher rcX RTOS versions prior to V2.1.14.1 allows for a denial of service due to incorrect verification of UDP packet length.

The Impact of CVE-2021-20988

The impact of this vulnerability is rated as HIGH with a base score of 8.6 (CVSS:3.1). The availability of the affected device can be significantly impacted.

Technical Details of CVE-2021-20988

This section provides more in-depth technical details of the vulnerability.

Vulnerability Description

The vulnerability arises from the lack of proper validation of the UDP packet length, which can be exploited to disrupt the affected device.

Affected Systems and Versions

Hilscher rcX RTOS versions prior to V2.1.14.1 are affected by this vulnerability.

Exploitation Mechanism

The vulnerability can be exploited by sending crafted UDP packets with incorrect lengths, leading to a denial of service.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-20988, immediate steps and long-term security practices should be adopted.

Immediate Steps to Take

Update the Hilscher rcX RTOS to version V2.1.14.1 or above to patch the vulnerability.
Implement network-level protections to filter out potentially malicious UDP packets.

Long-Term Security Practices

Regularly update and patch all software components to stay protected against vulnerabilities.
Conduct regular security audits and penetration testing to identify and address potential weaknesses.

Patching and Updates

Stay informed about security advisories from Hilscher and promptly apply recommended patches to secure your systems.