CVE-2020-12362 in Graphics Drivers
Summary
by MITRE • 02/17/2021
Integer overflow in the firmware for some Intel(R) Graphics Drivers for Windows * before version 26.20.100.7212 and before Linux kernel version 5.5 may allow a privileged user to potentially enable an escalation of privilege via local access.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 03/02/2021
This vulnerability represents a critical integer overflow flaw affecting Intel graphics drivers for windows and linux systems, specifically impacting firmware versions prior to 26.20.100.7212 and linux kernel versions before 5.5. The issue stems from improper handling of integer arithmetic within the graphics driver firmware, creating a condition where arithmetic operations exceed the maximum representable value for the data type, resulting in unexpected behavior. Such vulnerabilities are classified under CWE-191 Integer Underflow/Overflow, which is a common weakness in software systems where integer operations produce values outside the valid range for the data type. The vulnerability requires local access and privileged user privileges to exploit, making it particularly concerning for systems where administrative access is compromised or where privilege escalation is a primary attack vector. From an operational perspective, this flaw enables a malicious user with local access to potentially escalate privileges from standard user to administrator level, effectively bypassing system security controls and gaining unauthorized access to sensitive system resources. The attack surface is particularly broad given the widespread use of Intel graphics drivers across enterprise and consumer environments, making this vulnerability a significant concern for system administrators and security professionals. The exploitation process typically involves crafting specific input data that triggers the integer overflow condition, which then leads to memory corruption or unexpected program behavior that can be leveraged for privilege escalation. This type of vulnerability aligns with ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation', and T1547.001, which addresses 'Registry Run Keys / Startup Folder' as potential post-exploitation activities. The integer overflow occurs at the firmware level within the graphics driver component, making it particularly challenging to detect and mitigate as it operates below the operating system level and may not be visible through standard security monitoring tools. The vulnerability's impact is amplified by the fact that graphics drivers often run with elevated privileges and have direct access to hardware resources, providing a powerful attack surface for privilege escalation attacks.
The technical implementation of this vulnerability involves the manipulation of integer variables within the graphics driver firmware that handle buffer sizes, memory allocations, or other critical parameters. When these integers overflow, they can cause memory corruption that allows attackers to manipulate program flow or overwrite critical system data structures. The specific nature of the integer overflow suggests that the firmware performs calculations without proper bounds checking or overflow detection mechanisms, which is a fundamental security flaw in systems handling privileged operations. This type of vulnerability is particularly dangerous because it operates at a low level within the system architecture, often below the visibility of traditional security controls and monitoring systems. The vulnerability's existence demonstrates the critical importance of proper integer handling in firmware code, especially in components that interact with system-level resources and execute with elevated privileges. The exploitation typically requires a combination of local access and understanding of the specific firmware behavior, making it less likely to be exploited remotely but still highly dangerous in environments where local access is possible. Security researchers have noted that such integer overflow vulnerabilities often require careful analysis of the firmware code and specific input conditions to trigger the problematic behavior, which explains why these vulnerabilities may remain undetected for extended periods.
Mitigation strategies for this vulnerability primarily focus on updating to patched versions of both the Intel graphics drivers and the linux kernel, ensuring that all systems are running versions that contain the necessary fixes for the integer overflow condition. System administrators should prioritize patching these components as a high-priority security measure, particularly in enterprise environments where the risk of privilege escalation could result in significant data breaches or system compromise. The mitigation process should include comprehensive testing of patched drivers to ensure compatibility with existing hardware and software configurations, as graphics driver updates can sometimes introduce compatibility issues or performance regressions. Additional protective measures include implementing least privilege principles where possible, limiting local access to systems, and deploying enhanced monitoring for suspicious privilege escalation activities. Organizations should also consider implementing runtime protection mechanisms such as control flow integrity checks and address space layout randomization to make exploitation more difficult even if the vulnerability exists. The vulnerability highlights the critical need for regular security assessments of firmware components and the importance of maintaining up-to-date security patches across all system layers. Security teams should also conduct regular vulnerability assessments to identify similar integer overflow conditions in other system components and implement proper code review processes that include integer overflow detection. The incident underscores the necessity of maintaining comprehensive security monitoring that extends beyond traditional operating system level controls to include firmware-level activities and behavior analysis.