CVE-2020-15707 : Vulnerability Insights and Analysis

Integer overflows in GRUB2 could lead to a heap-based buffer overflow, affecting Ubuntu versions 20.04 LTS, 18.04 LTS, 16.04 LTS, and 14.04 ESM.

Understanding CVE-2020-15707

GRUB2 contained integer overflows in handling the initrd command, resulting in a heap-based buffer overflow.

What is CVE-2020-15707?

Integer overflows in functions of GRUB2 led to a heap-based buffer overflow in the efilinux component.
This vulnerability could be exploited by an attacker to execute arbitrary code and bypass UEFI Secure Boot restrictions.

The Impact of CVE-2020-15707

CVSS Base Score: 5.7 (Medium)
Attack Vector: Local
Attack Complexity: High
Privileges Required: High
Availability Impact: High
Integrity Impact: High

Technical Details of CVE-2020-15707

GRUB2 vulnerability details and affected systems.

Vulnerability Description

The issue stemmed from integer overflows in specific GRUB2 functions, leading to a heap-based buffer overflow.

Affected Systems and Versions

Ubuntu 20.04 LTS, 18.04 LTS, 16.04 LTS, and 14.04 ESM were impacted.

Exploitation Mechanism

Triggered by an excessive number of arguments to the initrd command on 32-bit architectures or crafted filesystems with large files.

Mitigation and Prevention

Protecting systems from CVE-2020-15707.

Immediate Steps to Take

Apply security patches provided by Ubuntu promptly.
Monitor vendor advisories for updates and follow best security practices.

Long-Term Security Practices

Regularly update GRUB2 and other software components to mitigate potential vulnerabilities.

Patching and Updates

Stay informed about security updates from Ubuntu and apply patches as soon as they are available.