CVE-2019-17211 Explained : Impact and Mitigation

A detailed overview of the integer overflow vulnerability in the CoAP library in Arm Mbed OS 5.14.0.

Understanding CVE-2019-17211

An explanation of the impact and technical details of the CVE-2019-17211 vulnerability.

What is CVE-2019-17211?

An integer overflow issue was identified in the CoAP library in Arm Mbed OS 5.14.0, specifically in the sn_coap_builder_calc_needed_packet_data_size_2() function.

The Impact of CVE-2019-17211

The vulnerability could result in insufficient buffer space allocation for CoAP messages due to an overflow in the returned_byte_count variable.

Technical Details of CVE-2019-17211

Insights into the vulnerability's description, affected systems, versions, and exploitation mechanism.

Vulnerability Description

The issue arises from the addition of two uint16_t values, potentially exceeding the maximum value and causing buffer space allocation problems.

Affected Systems and Versions

Affected Systems: Not applicable
Affected Versions: Arm Mbed OS 5.14.0

Exploitation Mechanism

The vulnerability occurs when the returned_byte_count surpasses the uint16_t limit, leading to inadequate memory allocation for CoAP messages.

Mitigation and Prevention

Guidance on immediate steps and long-term security practices to address CVE-2019-17211.

Immediate Steps to Take

Update to a patched version of Arm Mbed OS to mitigate the vulnerability.
Monitor for any unusual CoAP message behavior that could indicate exploitation.

Long-Term Security Practices

Regularly update software and firmware to prevent known vulnerabilities.
Implement secure coding practices to avoid integer overflow issues.

Patching and Updates

Ensure timely installation of security patches and updates to eliminate the vulnerability.