CVE-2025-21447 Overview
CVE-2025-21447 is a memory corruption vulnerability affecting multiple Qualcomm firmware components. The flaw occurs when the affected driver processes a device input/output control (IOCTL) call for session control. A local, authenticated attacker with low privileges can trigger the condition to corrupt kernel memory. Successful exploitation impacts confidentiality, integrity, and availability. The vulnerability is tracked under CWE-129: Improper Validation of Array Index. Qualcomm addressed the issue in its April 2025 security bulletin.
Critical Impact
Local low-privileged attackers can corrupt memory through a malicious IOCTL to session control, leading to potential code execution in a privileged context on affected Qualcomm chipsets.
Affected Products
- Qualcomm FastConnect 6900 and FastConnect 7800 (firmware and hardware)
- Qualcomm SC8380XP compute platform (firmware and hardware)
- Qualcomm WCD9380, WCD9385 audio codecs and WSA8840, WSA8845, WSA8845H smart speaker amplifiers
Discovery Timeline
- 2025-04-07 - CVE-2025-21447 published to NVD
- 2025-04 - Qualcomm publishes the April 2025 Security Bulletin containing the fix
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-21447
Vulnerability Analysis
The vulnerability resides in a Qualcomm driver that exposes IOCTL handlers for session control operations. When user-space software issues a device IOCTL with attacker-controlled parameters, the driver fails to validate an array index before using it. This improper validation (CWE-129) allows an out-of-bounds memory access that corrupts adjacent kernel structures.
Because the affected code runs in a privileged kernel context on the host operating system or on the connectivity/audio subsystem, memory corruption can escalate to arbitrary code execution at the same privilege level. All three security properties — confidentiality, integrity, and availability — are affected on successful exploitation.
Root Cause
The root cause is the absence of proper bounds validation on an array index derived from IOCTL input. The driver trusts the caller-supplied value and dereferences memory using this index during session control processing. Attackers who can open the device node and issue IOCTLs can trigger reads or writes outside allocated buffers.
Attack Vector
Exploitation requires local access to a device shipping the affected Qualcomm components, along with the ability to open the driver's device interface and issue IOCTLs. No user interaction is required. The attacker typically runs an unprivileged or low-privileged process, then submits crafted IOCTL requests to the session control handler to trigger memory corruption. Consult the Qualcomm Security Bulletin April 2025 for chipset-specific details.
Detection Methods for CVE-2025-21447
Indicators of Compromise
- Unexpected kernel panics, driver crashes, or reboots on devices using the affected Qualcomm firmware.
- Unprivileged processes opening Qualcomm driver device nodes and issuing unusual IOCTL sequences to session control interfaces.
- Kernel logs showing memory access faults originating from Qualcomm connectivity or audio subsystem drivers.
Detection Strategies
- Monitor endpoint telemetry for user-space processes performing atypical ioctl() calls against Qualcomm device nodes.
- Correlate kernel crash dumps with driver stack frames pointing at session control handlers in the affected components.
- Track OS and firmware patch levels across the fleet and flag devices missing the April 2025 Qualcomm patches.
Monitoring Recommendations
- Ingest kernel and driver crash telemetry from Windows on Snapdragon (SC8380XP) and Android endpoints into a centralized analytics platform.
- Alert on repeated privilege-boundary faults in Qualcomm drivers, which may indicate exploitation attempts.
- Baseline normal IOCTL usage for FastConnect and audio codec drivers so anomalous fuzzing-like patterns become visible.
How to Mitigate CVE-2025-21447
Immediate Actions Required
- Apply the OEM firmware and OS updates that incorporate Qualcomm's April 2025 security patches to all affected devices.
- Inventory endpoints containing FastConnect 6900/7800, SC8380XP, WCD9380/9385, or WSA8840/8845/8845H components and prioritize patching.
- Restrict local access on affected systems by enforcing least privilege and removing unnecessary local accounts.
Patch Information
Qualcomm released fixes as part of its April 2025 security bulletin. Device vendors integrate these updates into OEM firmware, Android security patch levels, and Windows on Snapdragon updates. Refer to the Qualcomm Security Bulletin April 2025 and coordinate with the device manufacturer for delivery schedules.
Workarounds
- No vendor-supplied workaround exists; patching is the required remediation path.
- Limit installation of untrusted local applications that could invoke driver IOCTLs on affected devices.
- Where feasible, apply application allowlisting to block unknown binaries from executing on devices pending firmware updates.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
