CVE-2024-21456: Qualcomm AR8035 Information Disclosure

CVE-2024-21456 Overview

CVE-2024-21456 is a critical information disclosure vulnerability affecting Qualcomm wireless chipset firmware. The vulnerability exists in the beacon frame parsing functionality within Station (STA) mode, where improper handling of buffer boundaries allows an attacker to read sensitive memory contents beyond intended boundaries. This out-of-bounds read vulnerability can expose sensitive system information and potentially cause denial of service conditions on affected devices.

The vulnerability affects a wide range of Qualcomm products including automotive platforms, 5G modem systems, and wireless connectivity solutions, making it particularly concerning for IoT devices, connected vehicles, and mobile infrastructure.

Critical Impact

Network-based attackers can exploit this vulnerability without authentication to disclose sensitive memory contents and potentially crash affected wireless chipsets, impacting a broad range of automotive and mobile devices.

Affected Products

• Qualcomm FastConnect 7800 Firmware
• Qualcomm Snapdragon Auto 5G Modem-RF Gen 2
• Qualcomm Snapdragon X72 5G Modem-RF System
• Qualcomm Snapdragon X75 5G Modem-RF System
• Qualcomm SA8775P (Automotive Platform)
• Qualcomm QCA6574/QCA6595/QCA6696 Series WiFi Chipsets
• Qualcomm AR8035 Ethernet Controller Firmware
• Qualcomm QCN6224/QCN6274 Series

Discovery Timeline

• July 1, 2024 - CVE-2024-21456 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2024-21456

Vulnerability Analysis

This vulnerability stems from improper buffer read operations during the parsing of 802.11 beacon frames when the wireless chipset is operating in Station (STA) mode. When a malformed beacon frame is received, the parsing routine fails to properly validate buffer boundaries before reading data elements, resulting in an out-of-bounds read condition (CWE-125, CWE-126).

The beacon frame parser processes various Information Elements (IEs) contained within the frame. When handling certain IEs with malformed length fields, the firmware may read beyond the allocated buffer, exposing adjacent memory regions that could contain sensitive cryptographic material, configuration data, or other system information.

Root Cause

The root cause is a buffer over-read vulnerability (CWE-126) combined with a general out-of-bounds read condition (CWE-125). The firmware's beacon frame parsing logic does not adequately validate the length fields within Information Elements before attempting to read the corresponding data. This allows a crafted beacon frame with excessive length values to trigger reads past the end of the allocated buffer.

Attack Vector

The attack can be executed over the network (wireless) without requiring any authentication or user interaction. An attacker within wireless range can broadcast malicious beacon frames containing crafted Information Elements with invalid length fields. When a vulnerable device's wireless chipset parses these frames, it reads beyond buffer boundaries, potentially:

1. Leaking sensitive memory contents back to the attacker through subsequent wireless communications
2. Causing memory access violations that crash the wireless subsystem
3. Exposing cryptographic keys, session tokens, or other sensitive data stored in adjacent memory

The attack is particularly dangerous in public WiFi environments, shared spaces, and automotive scenarios where attackers can establish proximity to vulnerable devices.

Detection Methods for CVE-2024-21456

Indicators of Compromise

• Unexpected wireless driver crashes or system instability when connecting to wireless networks
• Abnormal beacon frame activity with unusually large or malformed Information Elements in wireless traffic captures
• Memory dump artifacts indicating out-of-bounds read attempts in wireless firmware logs
• Repeated wireless subsystem restarts without user-initiated actions

Detection Strategies

• Implement wireless intrusion detection systems (WIDS) to monitor for anomalous beacon frame patterns and malformed 802.11 management frames
• Deploy network monitoring solutions that can identify beacon frames with suspicious IE length values or unusual frame structures
• Monitor device firmware logs for memory access violations or buffer-related errors in wireless components
• Utilize SentinelOne's endpoint detection capabilities to identify exploitation attempts targeting wireless subsystems

Monitoring Recommendations

• Enable verbose logging on wireless access points and controllers to capture detailed beacon frame information
• Implement automated alerting for devices experiencing repeated wireless driver failures or unexpected restarts
• Conduct periodic wireless spectrum analysis to identify rogue access points broadcasting potentially malicious beacon frames
• Deploy SentinelOne Singularity platform across endpoints to gain visibility into firmware-level anomalies and potential exploitation attempts

How to Mitigate CVE-2024-21456

Immediate Actions Required

• Apply firmware updates from Qualcomm as detailed in the Qualcomm Security Bulletin July 2024
• Inventory all devices containing affected Qualcomm chipsets including automotive systems, mobile devices, IoT equipment, and networking hardware
• Prioritize patching for devices deployed in high-risk environments such as public spaces, automotive fleets, and critical infrastructure
• Contact device OEMs to obtain updated firmware packages that include the security patches

Patch Information

Qualcomm has released security patches addressing this vulnerability as part of their July 2024 Security Bulletin. Organizations should obtain the appropriate firmware updates from their device manufacturers (OEMs) who integrate Qualcomm chipsets into their products.

Refer to the official Qualcomm Security Bulletin July 2024 for complete details on affected chipsets and firmware versions.

Workarounds

• Where possible, limit wireless connectivity to trusted networks and reduce exposure to potentially hostile wireless environments
• Implement wireless network segmentation to isolate vulnerable devices from critical systems until patches can be applied
• Consider disabling WiFi functionality on devices where wireless connectivity is not essential until firmware updates are available
• Deploy additional wireless monitoring infrastructure to detect potential exploitation attempts in environments with vulnerable devices

# Example: Check for Qualcomm chipset presence on Linux-based systems
lspci -v | grep -i qualcomm
lsusb | grep -i qualcomm
# Review wireless interface details
iw dev
# Check current firmware versions
ethtool -i wlan0 | grep -i firmware