CVE-2020-24165 in QEMU
Summary
by MITRE • 08/29/2023
An issue was discovered in TCG Accelerator in QEMU 4.2.0, allows local attackers to execute arbitrary code, escalate privileges, and cause a denial of service (DoS).
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/26/2024
The vulnerability identified as CVE-2020-24165 resides within the TCG Accelerator component of QEMU version 4.2.0, representing a critical security flaw that exposes virtualized environments to significant risks. This issue affects the TCG (Tiny Code Generator) accelerator which is responsible for translating virtual machine instructions into native machine code for improved performance. The vulnerability stems from inadequate input validation and memory management within the accelerator's code execution pathways, creating exploitable conditions that can be leveraged by local attackers with access to the virtualized system.
The technical flaw manifests through improper handling of memory operations during code generation and execution within the TCG subsystem. Attackers can manipulate specific input parameters that flow through the accelerator's translation routines, leading to memory corruption vulnerabilities that enable arbitrary code execution. This weakness operates at the intersection of multiple security domains including privilege escalation and denial of service conditions, as the vulnerability allows attackers to execute malicious code with elevated privileges within the guest operating system. The flaw particularly affects the memory management unit's handling of translated code blocks and can result in stack corruption, heap overflow, or instruction pointer manipulation that fundamentally compromises system integrity.
The operational impact of this vulnerability extends beyond simple code execution to encompass complete system compromise within virtualized environments. Local attackers with guest user privileges can leverage this vulnerability to escalate their privileges to host system level access, effectively breaking the isolation boundaries that separate virtual machines from each other and from the underlying host infrastructure. This represents a severe escalation of privilege vulnerability that aligns with CWE-121, heap-based buffer overflow, and CWE-122, stack-based buffer overflow, while also demonstrating characteristics of CWE-20, improper input validation. The denial of service component of this vulnerability can be exploited to crash the virtual machine or the entire host system, disrupting service availability and potentially causing data loss or system instability.
Mitigation strategies for CVE-2020-24165 require immediate patching of QEMU installations to versions that address the memory handling issues within the TCG accelerator. System administrators should implement mandatory updates to QEMU 4.2.1 or later versions that contain the necessary code modifications to prevent the exploitation pathways. Additionally, deployment of runtime monitoring solutions that can detect anomalous code execution patterns and memory corruption behaviors provides an additional layer of defense. The vulnerability's characteristics align with ATT&CK technique T1059.007, Command and Scripting Interpreter: PowerShell, when exploited through automated attack scripts, and T1068, Exploitation for Privilege Escalation, which directly addresses the privilege escalation capabilities. Organizations should also consider implementing virtual machine isolation measures and monitoring for unusual memory access patterns that could indicate exploitation attempts, as the vulnerability can be leveraged to establish persistent backdoors within virtualized environments.