CVE-2026-21376 Overview
CVE-2026-21376 is a memory corruption vulnerability affecting Qualcomm camera sensor driver firmware across multiple chipset platforms. The vulnerability occurs when the driver accesses an output buffer during IOCTL (Input/Output Control) processing without properly validating the buffer's size. This improper bounds checking can lead to out-of-bounds read operations, potentially exposing sensitive memory contents or causing system instability.
The vulnerability impacts a wide range of Qualcomm products including Snapdragon mobile platforms, compute platforms, FastConnect connectivity modules, and audio codecs. Given the local attack vector requiring low privileges, an attacker with limited access to an affected device could exploit this flaw to read sensitive kernel memory, escalate privileges, or cause denial of service conditions.
Critical Impact
Local attackers with low-level access can exploit this memory corruption flaw in Qualcomm camera sensor drivers to potentially achieve privilege escalation, information disclosure, or system crashes across numerous mobile and compute platforms.
Affected Products
- Qualcomm Snapdragon 8cx Gen 3 Compute Platform
- Qualcomm Snapdragon 8cx Gen 2 5G Compute Platform
- Qualcomm Snapdragon 7c/7c+ Gen 2 and Gen 3 Compute Platforms
- Qualcomm Snapdragon 460 and 662 Mobile Platforms
- Qualcomm FastConnect 6200/6700/6800/6900/7800
- Qualcomm QCM5430, QCM6490, SC8380XP, SM6250
- Qualcomm Video Collaboration VC3 Platform
- Qualcomm Snapdragon AR1 Gen 1 Platform
- Multiple WCD/WCN/WSA audio codec components
Discovery Timeline
- April 6, 2026 - CVE-2026-21376 published to NVD
- April 8, 2026 - Last updated in NVD database
Technical Details for CVE-2026-21376
Vulnerability Analysis
This vulnerability is classified as CWE-126 (Buffer Over-read), indicating that the camera sensor driver reads data past the end of the intended output buffer. The root cause lies in insufficient validation of buffer size parameters before memory access operations during IOCTL handling.
When a user-space application communicates with the camera sensor driver via IOCTL calls, the driver processes output buffers to return data. The vulnerable code path fails to verify that the provided buffer size is adequate to hold the output data, leading to potential out-of-bounds memory reads. This type of vulnerability can expose adjacent kernel memory contents, which may include sensitive data such as cryptographic keys, authentication tokens, or other privileged information.
The local attack vector means an attacker needs some level of access to the target device to exploit this vulnerability. However, the low privilege requirement indicates that even applications running in a restricted context could potentially trigger the vulnerable code path.
Root Cause
The vulnerability stems from missing size validation checks in the camera sensor driver's IOCTL handler. When the driver receives an IOCTL request with an output buffer, it should verify that the buffer size is sufficient before writing or reading data. The absence of this validation allows operations to proceed with undersized buffers, causing memory access beyond the allocated bounds.
This type of flaw commonly occurs when:
- Buffer size parameters are trusted without verification
- Length calculations do not account for edge cases
- Memory copy operations use user-supplied sizes directly
Attack Vector
The attack requires local access to a device running vulnerable Qualcomm firmware. An attacker could craft malicious IOCTL requests to the camera sensor driver with deliberately undersized output buffers. When the driver processes these requests without proper bounds checking, it may read beyond the buffer boundary, potentially:
- Leaking sensitive kernel memory to user space
- Causing memory corruption that could be leveraged for privilege escalation
- Triggering system crashes or denial of service
The exploitation mechanism involves sending crafted IOCTL commands to the camera driver device node (typically /dev/video* or similar) with parameters designed to trigger the buffer over-read condition. Since camera functionality is commonly available to applications, the attack surface is relatively accessible on affected devices.
Detection Methods for CVE-2026-21376
Indicators of Compromise
- Unexpected crashes or kernel panics related to camera sensor driver modules
- Anomalous IOCTL activity targeting camera device nodes with unusual buffer sizes
- Memory access violations logged in kernel message buffers involving camera driver components
- Suspicious applications attempting repeated camera driver interactions with varying parameters
Detection Strategies
- Monitor for applications sending IOCTL requests to camera device nodes with abnormally small buffer sizes
- Implement kernel-level auditing to track driver interactions, particularly for camera subsystem components
- Deploy endpoint protection capable of detecting exploitation attempts targeting driver vulnerabilities
- Review system logs for kernel warnings or errors referencing buffer overflows in camera-related modules
Monitoring Recommendations
- Enable kernel auditing for device node access patterns, especially for /dev/video* devices
- Monitor for processes making repeated camera driver IOCTL calls with error conditions
- Track firmware versions across device fleet to identify unpatched systems
- Implement behavioral analysis to detect anomalous application interactions with camera subsystems
How to Mitigate CVE-2026-21376
Immediate Actions Required
- Apply firmware updates from Qualcomm and device OEMs as soon as available
- Review device inventory to identify systems with affected Qualcomm chipsets
- Restrict unnecessary application access to camera functionality where possible
- Monitor affected devices for signs of exploitation attempts
Patch Information
Qualcomm has addressed this vulnerability in the April 2026 Security Bulletin. Device manufacturers (OEMs) are responsible for distributing firmware updates to end users. Organizations should:
- Check with device vendors for availability of security patches
- Prioritize updates for devices in high-risk environments
- Coordinate with mobile device management (MDM) solutions to expedite deployment
- Verify successful patch application through firmware version verification
Workarounds
- Limit camera access permissions to only trusted applications until patches can be applied
- Consider disabling or restricting camera functionality on high-value targets where feasible
- Implement application whitelisting to prevent unauthorized software from accessing camera interfaces
- Deploy enhanced monitoring on affected devices to detect potential exploitation attempts
# Example: Check Qualcomm firmware version on Android devices
adb shell getprop ro.board.platform
adb shell getprop ro.build.fingerprint
# Review camera driver module information
adb shell lsmod | grep cam
adb shell cat /proc/version
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
