CVE-2021-43619 : Exploit Details and Defense Strategies

Trusted Firmware M 1.4.x through 1.4.1 has a buffer overflow issue in the Firmware Update partition, allowing malicious actors to overwrite stack memory locations.

Understanding CVE-2021-43619

What is CVE-2021-43619?

Trusted Firmware M versions 1.4.x through 1.4.1 is susceptible to a buffer overflow vulnerability in the Firmware Update partition, enabling unauthorized modification of stack memory by specific callers in the IPC model.

The Impact of CVE-2021-43619

The vulnerability could be exploited by attackers to overwrite critical stack memory locations, potentially leading to arbitrary code execution and system compromise.

Technical Details of CVE-2021-43619

Vulnerability Description

Trusted Firmware M 1.4.x through 1.4.1 suffers from a buffer overflow issue in the Firmware Update partition. When a psa_fwu_write caller from SPE or NSPE interacts with the IPC model, it can maliciously overwrite stack memory locations.

Affected Systems and Versions

Product: Not applicable
Vendor: Not applicable
Versions affected: 1.4.x through 1.4.1

Exploitation Mechanism

The vulnerability arises from the improper handling of buffer sizes, allowing the psa_fwu_write caller in the IPC model to exceed memory boundaries and overwrite stack memory with malicious data.

Mitigation and Prevention

Immediate Steps to Take

Apply the provided patches and updates promptly to address the buffer overflow vulnerability.
Implement strict input validation mechanisms to prevent buffer overflow attacks.

Long-Term Security Practices

Conduct regular security assessments and code reviews to identify and remediate potential vulnerabilities.
Follow secure coding practices and enforce memory safety mechanisms to mitigate buffer overflow risks.

Patching and Updates

Regularly monitor and apply security updates from trusted sources to safeguard against known vulnerabilities in Trusted Firmware M.