CVE-2026-21385: Qualcomm Sm7675p Use-After-Free Flaw

CVE-2026-21385 Overview

CVE-2026-21385 is a memory corruption vulnerability affecting a wide range of Qualcomm chipsets and firmware. The vulnerability occurs when improper memory alignments are used during memory allocation operations, potentially leading to memory corruption conditions. This integer overflow vulnerability (CWE-190) enables a local attacker with low privileges to compromise the confidentiality, integrity, and availability of affected devices.

Critical Impact

This vulnerability is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, indicating active exploitation in the wild. Successful exploitation can result in arbitrary code execution, privilege escalation, or denial of service on affected Qualcomm-based devices including smartphones, automotive platforms, IoT devices, and wearables.

Affected Products

• Qualcomm Snapdragon 8 Gen 1/2/3 Mobile Platforms and Elite series
• Qualcomm Snapdragon 4/6/7 Gen series Mobile Platforms
• Qualcomm Automotive platforms (SA6155, SA8155, SA8255, SA8295, etc.)
• Qualcomm FastConnect WiFi/Bluetooth chipsets (6200, 6700, 6800, 6900, 7800)
• Qualcomm WCN connectivity chipsets (WCN3615 through WCN7881)
• Qualcomm Robotics platforms (RB2, RB5, Flight RB5 5G)
• Qualcomm XR/AR platforms (XR2, AR1 Gen 1)
• Qualcomm IoT and Vision Intelligence platforms

Discovery Timeline

• March 2, 2026 - CVE-2026-21385 published to NVD
• March 4, 2026 - Last updated in NVD database

Technical Details for CVE-2026-21385

Vulnerability Analysis

This memory corruption vulnerability stems from improper handling of memory alignment values during allocation operations within Qualcomm firmware. The flaw is classified as an Integer Overflow (CWE-190), where arithmetic operations on alignment values can exceed the maximum representable value, wrapping around to produce unexpectedly small allocation sizes.

When a malicious application or process provides specially crafted alignment parameters, the integer overflow condition can cause the firmware to allocate a buffer that is significantly smaller than intended. Subsequent memory operations that assume the expected buffer size will then write beyond the allocated boundary, corrupting adjacent memory regions.

The vulnerability requires local access to the device and low privileges to exploit, but no user interaction is needed. This makes it particularly dangerous for scenarios where an attacker has already achieved initial access through another vector, as CVE-2026-21385 can serve as a privilege escalation mechanism.

Root Cause

The root cause is an integer overflow condition (CWE-190) in the memory allocation alignment handling code. When alignment values are processed without proper bounds checking, arithmetic operations can overflow, resulting in:

1. Allocation of undersized memory buffers
2. Subsequent out-of-bounds memory writes when the buffer is used
3. Corruption of adjacent heap metadata or application data structures
4. Potential for controlled memory corruption leading to code execution

The widespread impact across Qualcomm's product portfolio suggests the vulnerable code resides in a shared firmware component used across mobile, automotive, IoT, and connectivity chipsets.

Attack Vector

The attack vector is local, requiring an attacker to execute code on the target device. This could be achieved through:

1. A malicious application installed on the device
2. Exploitation of another vulnerability providing initial code execution
3. Physical access to the device with debugging capabilities enabled

Once the attacker can execute code locally, they can invoke the vulnerable memory allocation routines with crafted alignment parameters to trigger the integer overflow. The resulting memory corruption can be leveraged to overwrite critical data structures, manipulate function pointers, or achieve arbitrary code execution with elevated privileges.

The vulnerability mechanism involves providing alignment values that, when used in arithmetic calculations, overflow and wrap to small values. For detailed technical information, refer to the Qualcomm March 2026 Security Bulletin.

Detection Methods for CVE-2026-21385

Indicators of Compromise

• Unexpected system crashes or kernel panics related to memory allocation failures
• Anomalous memory allocation patterns with unusually small buffer sizes following large alignment requests
• Suspicious processes attempting to trigger specific system calls related to memory management
• Evidence of heap corruption or memory metadata manipulation in crash dumps

Detection Strategies

• Monitor for applications making unusual memory allocation requests with large alignment parameters
• Deploy runtime memory corruption detection tools on Android devices where supported
• Implement anomaly detection for processes exhibiting signs of exploitation attempts
• Review system logs for repeated memory-related errors that could indicate exploitation attempts

Monitoring Recommendations

• Enable and collect Android system logs for memory-related warnings and errors
• Monitor application behavior for signs of privilege escalation post-installation
• Implement mobile device management (MDM) solutions to detect devices running unpatched firmware
• Use SentinelOne Mobile Threat Defense to identify applications exhibiting suspicious memory manipulation behavior

How to Mitigate CVE-2026-21385

Immediate Actions Required

• Apply the March 2026 Android Security Bulletin patches immediately to all affected devices
• Prioritize patching for devices in sensitive environments given the known exploitation status
• Review installed applications and remove any suspicious or unauthorized software
• Enable additional security controls through MDM solutions while patches are deployed

Patch Information

Qualcomm has released firmware updates addressing this vulnerability as documented in the Qualcomm March 2026 Security Bulletin. The patches have been integrated into the Android March 2026 Security Bulletin.

Device manufacturers (OEMs) are responsible for delivering these patches to end-user devices. Organizations should work with their device vendors to ensure timely patch delivery and deployment. For automotive and IoT deployments, coordinate with Qualcomm or your system integrator for firmware update availability.

Workarounds

• Restrict installation of applications to trusted sources only (enterprise app stores, verified publishers)
• Implement application allowlisting to prevent unauthorized code execution on managed devices
• Enable SELinux enforcing mode on Android devices to limit exploitation impact
• Isolate unpatched devices from sensitive network segments until patches can be applied

# Verify Android security patch level on device
adb shell getprop ro.build.version.security_patch
# Expected output should be 2026-03-01 or later for full protection