CVE-2024-23373 Overview
CVE-2024-23373 is a Use-After-Free (UAF) memory corruption vulnerability affecting a broad range of Qualcomm chipset firmware. The vulnerability occurs when an IOMMU (Input-Output Memory Management Unit) unmap operation fails, leading to the premature release of DMA (Direct Memory Access) and anonymous buffers while they may still be in use by the system.
This vulnerability poses significant risk to devices utilizing affected Qualcomm processors, including smartphones, IoT devices, automotive platforms, wearables, and extended reality (XR) systems. Successful exploitation could allow a local attacker with low privileges to achieve arbitrary code execution, data exfiltration, or complete system compromise.
Critical Impact
A local attacker could exploit this memory corruption flaw to execute arbitrary code with elevated privileges, potentially gaining full control over affected devices including mobile phones, automotive systems, and IoT devices.
Affected Products
- Qualcomm Snapdragon 8 Gen 1/2/3 Mobile Platforms
- Qualcomm Snapdragon 865/888 5G Mobile Platforms
- Qualcomm SA8155P/SA8195P/SA8255P Automotive Platforms
- Qualcomm FastConnect 6700/6800/6900/7800 Connectivity Solutions
- Qualcomm QCS8550/QCM8550 IoT Platforms
- Qualcomm Snapdragon XR2 5G Platform
- Qualcomm Robotics RB3/RB5 Platforms
Discovery Timeline
- July 1, 2024 - CVE-2024-23373 published to NVD
- November 21, 2024 - Last updated in NVD database
Technical Details for CVE-2024-23373
Vulnerability Analysis
This Use-After-Free vulnerability (CWE-416) resides in the IOMMU subsystem of Qualcomm firmware. The IOMMU is responsible for managing memory access between hardware peripherals and system memory, providing address translation and memory isolation for DMA operations.
When a DMA buffer is allocated for device operations, the IOMMU creates mappings that allow peripheral hardware to access specific memory regions. Under normal circumstances, when these buffers are no longer needed, the IOMMU performs an unmap operation to release the mappings before the memory is freed.
The vulnerability occurs in error handling paths where an IOMMU unmap operation fails. Despite the failure, the code path continues to release both DMA and anonymous buffers. This creates a dangerous condition where memory is freed while the IOMMU mappings may still reference it, or while other components may still expect the buffers to be valid.
The flaw requires local access and low privileges to trigger. An attacker who can execute code on the device could craft specific sequences of memory allocation and deallocation operations to trigger the race condition, potentially allowing them to achieve high impact on confidentiality, integrity, and availability of the affected system.
Root Cause
The root cause is improper error handling in the IOMMU unmap failure path. When the unmap operation fails, the system should either retry the operation, maintain buffer validity until successful cleanup, or invoke a safe failure state. Instead, the current implementation proceeds to free the buffers regardless of the unmap failure status, creating a classic Use-After-Free condition.
This type of error handling deficiency is particularly dangerous in memory management subsystems where precise synchronization between different components (IOMMU, DMA controller, memory allocator) is critical for system stability and security.
Attack Vector
The vulnerability requires local access to the affected device. An attacker would need to execute code locally (such as through a malicious application or by exploiting another vulnerability for initial access) to exploit this flaw.
The attack would involve:
- Triggering allocation of DMA/anonymous buffers through legitimate system interfaces
- Forcing conditions that cause IOMMU unmap operations to fail (such as resource exhaustion or specific timing conditions)
- Observing when the buffers are prematurely freed despite the unmap failure
- Reusing the freed memory through controlled allocations to achieve code execution or data manipulation
The vulnerability is particularly concerning given its presence across a wide range of Qualcomm products spanning mobile, automotive, IoT, and XR platforms. This breadth of affected products means billions of devices worldwide could potentially be impacted.
Detection Methods for CVE-2024-23373
Indicators of Compromise
- Unexpected kernel panics or system crashes related to IOMMU or DMA operations
- Memory corruption errors in kernel logs referencing freed memory regions
- Anomalous behavior in applications that heavily utilize DMA operations (graphics, camera, modem)
- Unexpected process memory access patterns detected by memory protection mechanisms
Detection Strategies
- Monitor for kernel log entries indicating IOMMU unmap failures followed by memory access violations
- Implement memory debugging tools (such as KASAN) during device testing to detect Use-After-Free conditions
- Deploy endpoint detection solutions capable of monitoring kernel-level memory operations
- Use hardware security features like ARM Memory Tagging Extension (MTE) where available to detect memory corruption
Monitoring Recommendations
- Enable verbose kernel logging for IOMMU subsystem events on development and test devices
- Implement crash analytics to identify patterns consistent with memory corruption exploitation
- Monitor for applications requesting unusual DMA buffer allocation patterns
- Track firmware versions across device fleet to ensure timely patch deployment
How to Mitigate CVE-2024-23373
Immediate Actions Required
- Review Qualcomm's July 2024 Security Bulletin for affected products and available patches
- Contact device OEMs for firmware update availability timelines
- Prioritize patching for devices in high-security environments (automotive, enterprise mobile)
- Limit installation of untrusted applications on affected devices until patches are applied
- Enable all available exploit mitigation technologies on affected platforms
Patch Information
Qualcomm has disclosed this vulnerability in their July 2024 Security Bulletin. Organizations should work with their device manufacturers (OEMs) to obtain firmware updates that include the fix for CVE-2024-23373. Given the extensive list of affected chipsets, updates will be distributed through various channels depending on the product category:
- Mobile devices: Updates typically delivered through Android Security Bulletins and OEM update channels
- Automotive platforms: Coordinate with automotive suppliers for in-vehicle system updates
- IoT devices: Work with solution providers for firmware update availability
Workarounds
- Restrict device access to trusted users and applications until patches can be applied
- Enable any available sandboxing or isolation features to limit the impact of exploitation
- Implement network segmentation for IoT and automotive devices to contain potential breaches
- Monitor devices for signs of exploitation and prepare incident response procedures
# Check device firmware version on Android devices
adb shell getprop ro.build.fingerprint
adb shell getprop ro.build.version.security_patch
# Verify Qualcomm chipset information
adb shell cat /proc/cpuinfo | grep Hardware
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
