USN-6920-1: EDK II vulnerabilities - Understanding the Risks

In our modern digital age, the backbone of computer system security often rests in the underlying firmware and software that runs before any operating system is even loaded. EDK II, a part of the TianoCore project, which provides firmware development tools for UEFI/PI firmware, is no exception. The integrity of this firmware is crucial because it interfaces directly with the tricky interstice of hardware-level operations and high-level software functionality.

Recently, several vulnerabilities in EDK II have come to light, under security alert USN-6920-1. These issues cover a breadth of problems, ranging from insufficient bounds checks in Tianocompress to improper memory handling in system firmware. Here, we delve into these vulnerabilities, explore the associated risks, and understand the essential steps for mitigation to help protect your systems.

Overview of Discovered Vulnerabilities

Outlined below is a list of the specific CVEs reported under alert USN-6920-1, detailing their nature and the potential risks they pose:

  • CVE-2017-5731: Before November 7, 2017, Tianocompress lacked sufficient bounds checks, potentially leading to buffer overflow and privilege escalation through local access by an authenticated user.
  • CVE-2018-12182: An insufficient memory write check in the SMM service can cause a page fault, leading to privilege escalation, information disclosure, or denial of service through local access by an authenticated user.
  • CVE-2018-12183: Improper handling of memory in DxeCore could result in a stack overflow, enabling unauthenticated users to escalate privileges or cause information disclosure and denial of service via local access.
  • CVE-2018-3613: A logical flaw in the Variable service could lead to privilege escalation, information disclosure, and denial of service via local access by an authenticated user.
  • CVE-2019-0160: A buffer overflow in the system firmware could enable network-based attacks by unauthenticated users leading to privilege escalation or denial of service.

Understanding the Implications

These vulnerabilities, if exploited, could allow attackers varying degrees of control over the compromised system. This can range from unauthorized data access to complete system compromise. Since these vulnerabilities affect the firmware layer, their exploitation can subvert traditional security measures like operating system-level defenses and antivirus programs.

Protection Measures

It’s crucial to note that measures do exist to mitigate these risks. Here are steps to safeguard your systems:

  • Regular System Updates: Keep your system firmware and related components updated to the latest versions. Firmware updates often contain patches for these vulnerabilities.
  • Secure Configuration: Ensure that system firmware settings are configured to enhance security. This might include disabling unnecessary services or features that could be exploited if vulnerable.
  • User Education and Access Management: Train users on the importance of security practices and implement strict access controls to limit exposure to attacks.

In conclusion, while the vulnerabilities in EDK II present significant security challenges, understanding and addressing them proactively can vastly reduce the risk of exploitation. For a deeper dive into these vulnerabilities and more detailed guidance on mitigating risks, visit LinuxPatch.com.