CVE-2020-11261: Qualcomm Apq8009 Buffer Overflow Flaw

CVE-2020-11261 Overview

CVE-2020-11261 is a memory corruption vulnerability affecting a wide range of Qualcomm Snapdragon chipsets used across mobile devices, automotive systems, IoT devices, wearables, and computing platforms. The vulnerability occurs due to improper input validation when a user application requests memory allocation of an excessively large size. The system fails to properly return an error condition, leading to memory corruption that can potentially be exploited by an attacker with local access to achieve code execution or escalate privileges.

This vulnerability is particularly concerning due to the ubiquitous nature of Qualcomm's Snapdragon platform, which powers billions of devices worldwide across multiple market segments including smartphones, connected vehicles, industrial IoT equipment, and wearable technology.

Critical Impact

This vulnerability has been confirmed as actively exploited in the wild and is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, requiring immediate attention for organizations using affected Qualcomm chipsets.

Affected Products

• Qualcomm Snapdragon Auto platforms (SA6155, SA8155 series)
• Qualcomm Snapdragon Mobile platforms (SD660, SD835, SD845, SD855, SD865 5G, SD888 5G series)
• Qualcomm Snapdragon Compute platforms (SD 8cx, SD 8c series)
• Qualcomm Snapdragon Connectivity platforms (QCA6390, WCN3990, WCN6850 series)
• Qualcomm Snapdragon Consumer IOT and Industrial IOT platforms (QCS405, QCS605, QCS610 series)
• Qualcomm Snapdragon Voice & Music platforms (APQ8009, CSRA6620, WCD9340 series)
• Qualcomm Snapdragon Wearables platforms (MSM8909W, SDM429W, SDW3100 series)

Discovery Timeline

• June 9, 2021 - CVE-2020-11261 published to NVD
• October 28, 2025 - Last updated in NVD database

Technical Details for CVE-2020-11261

Vulnerability Analysis

This vulnerability is classified as an improper input validation flaw (CWE-20) that leads to an out-of-bounds write condition (CWE-787). The core issue exists in the memory allocation handling within Qualcomm's graphics driver subsystem. When a user-space application requests memory allocation with an abnormally large size parameter, the vulnerable code path fails to properly validate this input and return an appropriate error.

The vulnerability requires local access to exploit, meaning an attacker would need to execute code on the target device, typically through a malicious application. However, the low attack complexity and the ability to achieve complete confidentiality, integrity, and availability impact make this a serious threat, particularly on mobile devices where users frequently install third-party applications.

Given that this vulnerability has been confirmed as actively exploited and is listed in the CISA KEV catalog, organizations should treat remediation as a high priority.

Root Cause

The root cause lies in insufficient bounds checking within the memory allocation request handling code in Qualcomm's GPU driver. When processing memory allocation requests from user space, the driver fails to validate that the requested size is within acceptable limits before proceeding with the allocation. This missing validation allows a specially crafted request with an extremely large size value to bypass normal safety checks.

The improper validation causes the system to enter an unexpected state where memory operations occur outside of intended boundaries, leading to memory corruption. This corruption can be leveraged by attackers to overwrite critical data structures, potentially achieving arbitrary code execution with elevated privileges.

Attack Vector

The attack vector for CVE-2020-11261 is local, requiring an attacker to execute code on the target device. This is typically achieved through a malicious application installed by the user. Once executed, the attack proceeds as follows:

The malicious application makes an ioctl call to the GPU driver, requesting memory allocation with an oversized parameter. Due to the missing validation, this request is processed without proper error handling. The resulting memory corruption can then be exploited to achieve various outcomes including privilege escalation from application context to kernel context, or arbitrary code execution.

On mobile devices, this attack chain could allow a seemingly benign application to gain root-level access, enabling data theft, persistent malware installation, or complete device compromise. For automotive and industrial IoT deployments, successful exploitation could have safety-critical implications.

Detection Methods for CVE-2020-11261

Indicators of Compromise

• Unusual memory allocation patterns or excessive memory requests from applications targeting the GPU driver
• System crashes or kernel panics related to graphics driver operations with error messages indicating memory allocation failures
• Applications requesting unusually large memory allocations through GPU-related system calls
• Anomalous process behavior following interaction with graphics subsystems, particularly privilege changes or unexpected child process spawning

Detection Strategies

• Monitor system logs for graphics driver errors indicating failed large memory allocations or out-of-bounds access attempts
• Implement application behavior monitoring to detect abnormal ioctl patterns to GPU device nodes such as /dev/kgsl-3d0
• Deploy endpoint detection solutions capable of identifying memory corruption exploitation techniques at the kernel level
• Review installed applications on affected devices for known malware signatures or suspicious permissions related to graphics operations

Monitoring Recommendations

• Enable kernel auditing to capture ioctl calls to graphics driver subsystems on affected Android devices
• Implement memory allocation monitoring to alert on requests exceeding normal operational thresholds
• Monitor for processes attempting to access GPU memory regions outside their allocated space
• Track firmware versions across device fleet to ensure timely identification of unpatched systems

How to Mitigate CVE-2020-11261

Immediate Actions Required

• Apply the latest security updates from device manufacturers that include the Qualcomm January 2021 security patches
• Audit all devices with affected Qualcomm chipsets and prioritize patching based on exposure and criticality
• For devices where patches are not yet available, consider restricting untrusted application installation
• Review installed applications on affected devices and remove any that are not from trusted sources
• For automotive and industrial deployments, coordinate with Qualcomm and system integrators for appropriate firmware updates

Patch Information

Qualcomm addressed this vulnerability in their January 2021 Security Bulletin. Device manufacturers subsequently released patches through their standard update channels. For Android devices, users should ensure they have installed all available security updates from their device manufacturer.

Due to the confirmed active exploitation of this vulnerability, CISA has added CVE-2020-11261 to their Known Exploited Vulnerabilities Catalog, mandating federal agencies to apply patches within specified timeframes. Organizations should follow similar urgency in their remediation efforts.

Workarounds

• Restrict installation of applications to only verified, trusted sources (e.g., official app stores) to reduce the risk of malicious applications exploiting this vulnerability
• Implement Mobile Device Management (MDM) solutions to control application installation and enforce security policies on affected devices
• For enterprise environments, consider network segmentation to limit the impact of potentially compromised devices
• Deploy endpoint protection solutions with behavior-based detection capabilities to identify exploitation attempts

# Check Android device security patch level
adb shell getprop ro.build.version.security_patch
# Devices should show 2021-01-05 or later to include this fix

# List installed Qualcomm-related kernel modules (for diagnostics)
adb shell lsmod | grep -i "kgsl\|adreno\|msm"