CVE-2021-43666 Explained : Impact and Mitigation

A Denial of Service vulnerability exists in mbed TLS 3.0.0 and earlier in the mbedtls_pkcs12_derivation function when an input password's length is 0.

Understanding CVE-2021-43666

A Denial of Service vulnerability in mbed TLS due to a specific issue with the mbedtls_pkcs12_derivation function.

What is CVE-2021-43666?

The vulnerability occurs in mbed TLS versions 3.0.0 and earlier, specifically in the mbedtls_pkcs12_derivation function when processing an input password with a length of 0.

The Impact of CVE-2021-43666

The vulnerability can be exploited to cause a Denial of Service condition, potentially disrupting the normal operation of systems utilizing the affected versions of mbed TLS.

Technical Details of CVE-2021-43666

Details about the technical aspects of the vulnerability.

Vulnerability Description

The issue lies in the mbedtls_pkcs12_derivation function within mbed TLS, triggered by an input password of length 0, leading to a Denial of Service risk.

Affected Systems and Versions

Affected Version: mbed TLS 3.0.0 and earlier
Vendor: n/a
Product: n/a

Exploitation Mechanism

Attackers can exploit this vulnerability by providing a specially crafted input password of length 0 to trigger the issue within the mbedtls_pkcs12_derivation function.

Mitigation and Prevention

Ways to address and prevent the CVE-2021-43666 vulnerability.

Immediate Steps to Take

Upgrade to a patched version of mbed TLS that addresses the vulnerability.
Apply security best practices to restrict unauthorized access to the affected systems.

Long-Term Security Practices

Regularly update and patch software components to mitigate potential vulnerabilities.
Implement network security measures to detect and prevent DoS attacks.

Patching and Updates

Ensure prompt installation of security updates and patches released by the mbed TLS project to remediate the CVE-2021-43666 vulnerability.