CVE-2020-24658 : Security Advisory and Response

Arm Compiler 5 through 5.06u6 has a vulnerability in its stack protection feature that may lead to stack-based buffer overflows.

Understanding CVE-2020-24658

This CVE describes an issue in Arm Compiler 5 that affects the stack protection mechanism, potentially allowing for stack-based buffer overflows.

What is CVE-2020-24658?

The vulnerability in Arm Compiler 5 involves errors in the stack protection feature designed to detect stack-based buffer overflows in local arrays. When this feature is active, a protected function writes a guard value to the stack above any vulnerable arrays. If both the reference value and the guard value are written to the stack, the protection mechanism may fail to detect corruption when both values are overwritten with the same value.

The Impact of CVE-2020-24658

The vulnerability could be exploited to bypass stack protection mechanisms, potentially leading to unauthorized access, data corruption, or system crashes.

Technical Details of CVE-2020-24658

Arm Compiler 5 through 5.06u6 is affected by a vulnerability in its stack protection feature.

Vulnerability Description

The stack protection feature in Arm Compiler 5 is designed to detect stack-based buffer overflows in local arrays.
Writing both the reference value and the guard value to the stack may lead to a failure in corruption detection.

Affected Systems and Versions

Product: Arm Compiler 5
Vendor: Arm
Versions: All versions up to 5.06u6

Exploitation Mechanism

A buffer overflow and underflow in vulnerable arrays could corrupt both the reference and guard values on the stack, bypassing the protection.

Mitigation and Prevention

Steps to address and prevent the CVE-2020-24658 vulnerability.

Immediate Steps to Take

Disable the stack protection feature in Arm Compiler 5 if possible.
Monitor for any unusual behavior or system crashes that may indicate exploitation.

Long-Term Security Practices

Regularly update the compiler to the latest version to patch known vulnerabilities.
Implement secure coding practices to minimize the risk of buffer overflows and other vulnerabilities.

Patching and Updates

Arm has released security updates to address this vulnerability. Ensure you apply the latest patches to protect your systems.