A critical security flaw in Qualcomm's Adreno GPU drivers has been discovered that allows attackers to gain complete control over Android devices by directly manipulating physical memory—bypassing virtually all modern security protections.
CVE-2025-21479, patched in Qualcomm's June security bulletin, affects the Adreno A7xx series GPUs found in premium Android smartphones, including Samsung Galaxy S24 devices. The vulnerability exploits a fundamental logic error in the GPU's microcode that incorrectly grants the highest-level privileges to user applications.
The "Nuclear Bomb" Vulnerability
Security researchers describe this flaw as a "nuclear bomb" case due to its unprecedented impact. Unlike typical exploits that must navigate complex software mitigations like KASLR (Kernel Address Space Layout Randomization) and DEP (Data Execution Prevention), CVE-2025-21479 allows attackers to simply "rewrite physical memory" directly.
The bug stems from outdated permission checking logic in GPU firmware. When Qualcomm expanded its instruction buffer architecture from four to five levels with the A7xx series, it failed to update the microcode accordingly. This causes the system to mistakenly grant Ring 0 (highest privilege) access when executing commands at the lowest privilege level.
"5 of the 7 Android 0-days from 2021 targeted GPU drivers," according to Google's Project Zero team, highlighting the growing threat landscape around graphics processors that now handle far more than just rendering—including machine learning, image processing, and security-critical operations.
Exploitation Process
Attackers can exploit this vulnerability by manipulating the GPU's memory management unit, allowing them to configure malicious page tables and achieve arbitrary physical memory read/write capabilities. This enables them to locate and modify critical kernel data structures, disable SELinux security policies, and ultimately gain root privileges.
The exploit is particularly dangerous because it can bypass advanced protection mechanisms like Samsung's KNOX and Huawei's HKIP by targeting policy data rather than protected code segments.
Protection Measures
Qualcomm has released firmware updates addressing this vulnerability. Users should immediately install the latest security patches from their device manufacturers. The flaw affects multiple flagship Android devices, making widespread patching critical for maintaining mobile security.
This incident underscores the evolving attack surface in mobile devices, where GPUs have become powerful "second brains" that require equal security attention as traditional CPU-focused protections.