CVE-2023-33063: Qualcomm 315 5G IoT Use-After-Free Flaw

CVE-2023-33063 Overview

CVE-2023-33063 is a Use After Free (UAF) memory corruption vulnerability affecting Qualcomm DSP (Digital Signal Processor) Services. The vulnerability occurs during remote calls from the High-Level Operating System (HLOS) to the DSP, allowing attackers with local access to potentially execute arbitrary code, gain elevated privileges, or cause system instability on affected devices.

This vulnerability is particularly concerning due to its presence across a vast range of Qualcomm chipsets powering smartphones, IoT devices, automotive systems, and networking equipment. The local attack vector requires an attacker to have some level of access to the device, but the low complexity and lack of required user interaction make exploitation relatively straightforward once initial access is obtained.

Critical Impact

This vulnerability is actively exploited in the wild and has been added to CISA's Known Exploited Vulnerabilities (KEV) catalog. Successful exploitation can lead to complete confidentiality, integrity, and availability compromise of affected systems.

Affected Products

• Qualcomm Snapdragon Mobile Platforms (210, 212, 425, 429, 439, 625, 632, 662, 675, 8 Gen 2, 8+ Gen 2 series)
• Qualcomm Snapdragon Automotive Platforms (SA4150P, SA6155P, SA8155P, SA8775P series)
• Qualcomm Wireless Connectivity Chipsets (WCN3xxx, WCN6xxx, WCN7xxx, QCA6xxx series)
• Qualcomm IPQ Networking Processors (IPQ4xxx, IPQ5xxx, IPQ6xxx, IPQ8xxx series)
• Qualcomm Snapdragon XR and Wearable Platforms (XR1, XR2, W5+, Wear 4100+ series)
• Qualcomm Modem-RF Systems (X12, X24, X50, X55, X65 5G modems)
• Qualcomm IoT and Embedded Platforms (315 5G IoT Modem, Vision Intelligence, Video Collaboration platforms)

Discovery Timeline

• December 5, 2023 - CVE-2023-33063 published to NVD
• October 27, 2025 - Last updated in NVD database

Technical Details for CVE-2023-33063

Vulnerability Analysis

This Use After Free vulnerability exists within Qualcomm's DSP Services component, which facilitates communication between the High-Level Operating System (such as Android) and the dedicated Digital Signal Processor. The DSP handles computationally intensive tasks including audio processing, image processing, machine learning inference, and sensor data handling.

During remote procedure calls from the HLOS to the DSP, a race condition or improper memory management can lead to a situation where memory is freed but subsequently referenced. When this freed memory is reallocated for other purposes, the continued use of stale pointers can result in memory corruption.

The vulnerability requires local access to the device, meaning an attacker must either have physical access or have already compromised the device through another vector (such as a malicious application). Once exploited, the attacker can achieve arbitrary code execution within the context of the DSP services, potentially gaining kernel-level privileges on the affected device.

Root Cause

The root cause is a Use After Free (CWE-416) condition in the DSP Services memory management. When processing remote calls from HLOS to DSP, the service fails to properly track the lifecycle of allocated memory objects. This results in scenarios where:

1. A memory object is allocated for a DSP service request
2. The object is freed prematurely or under certain race conditions
3. The freed memory pointer is subsequently dereferenced
4. An attacker can manipulate the freed memory to contain malicious data, leading to code execution

Attack Vector

The attack requires local access to the device with low privileges and no user interaction. An attacker can exploit this vulnerability through:

1. Malicious Application: A rogue Android application requesting DSP services can craft specific sequences of calls designed to trigger the use-after-free condition
2. Privileged Process Exploitation: An attacker with access to system processes can directly interact with DSP service interfaces
3. Chained Exploitation: This vulnerability can be chained with other local vulnerabilities to escalate privileges from application-level access to kernel control

The exploitation mechanism involves manipulating the timing and sequence of DSP service calls to create a race condition where memory is freed while still being referenced by active operations. By controlling the contents of the reallocated memory region, attackers can redirect execution flow to attacker-controlled code.

Detection Methods for CVE-2023-33063

Indicators of Compromise

• Unusual DSP service crashes or system instability related to audio/video/sensor processing
• Unexpected privilege escalation events or processes gaining elevated permissions
• Abnormal memory access patterns in kernel logs related to adsprpc or fastrpc services
• Suspicious applications making excessive or unusual DSP service calls

Detection Strategies

• Monitor for abnormal behavior in DSP-related system services and kernel modules
• Implement runtime application self-protection (RASP) to detect exploitation attempts
• Deploy mobile threat defense solutions capable of detecting kernel-level compromise
• Analyze application permissions and behavior for excessive DSP service interactions

Monitoring Recommendations

• Enable enhanced kernel logging for DSP service interactions on Android devices
• Implement anomaly detection for unusual patterns in audio/video processing pipelines
• Monitor for applications requesting unnecessary permissions related to DSP services
• Deploy endpoint detection and response (EDR) solutions with mobile device support

How to Mitigate CVE-2023-33063

Immediate Actions Required

• Apply the December 2023 security patches from Qualcomm and device OEMs immediately
• Verify device firmware versions include the fix for CVE-2023-33063
• Remove or disable untrusted applications that may attempt exploitation
• Implement network segmentation for IoT and automotive devices with affected chipsets

Patch Information

Qualcomm has addressed this vulnerability in the December 2023 Security Bulletin. Device manufacturers (OEMs) must integrate these patches into their firmware updates. Users should:

1. Check with their device manufacturer for available security updates
2. For Android devices, ensure the December 2023 or later Android Security Patch Level is installed
3. For IoT and automotive platforms, contact the vendor for firmware update availability
4. Monitor the CISA KEV Catalog for updated remediation guidance

Workarounds

• Restrict installation of applications to trusted sources only (official app stores)
• Enable application sandboxing and strict SELinux policies where available
• For enterprise deployments, implement mobile device management (MDM) to enforce security policies
• Consider network-level protections to limit lateral movement if a device is compromised

# Android Security Patch verification
# Check current security patch level on Android devices
adb shell getprop ro.build.version.security_patch
# Should return 2023-12-01 or later for patched devices

# Verify DSP service status (requires root)
adb shell cat /proc/modules | grep -i "adsprpc\|fastrpc"