CVE-2025-27047: Qualcomm Fastconnect Use After Free Flaw

CVE-2025-27047 Overview

CVE-2025-27047 is a memory corruption vulnerability affecting a broad range of Qualcomm chipsets and firmware components. The flaw resides in the handling of the TESTPATTERNCONFIG escape path within Qualcomm graphics driver code. A local, authenticated attacker can trigger the condition to corrupt memory, potentially achieving code execution in a privileged context. The weakness is categorized under CWE-416: Use After Free, and impacts FastConnect wireless modules, WCD audio codecs, WSA smart speaker amplifiers, and Snapdragon compute platforms. Qualcomm addressed the issue in the Qualcomm July 2025 Security Bulletin.

Critical Impact
Successful exploitation results in high-impact loss of confidentiality, integrity, and availability on affected devices, enabling privilege escalation from a local, low-privileged process.

Affected Products

Qualcomm FastConnect 6700, 6900, and 7800 firmware
Qualcomm QCM5430, QCM6490, QCS5430, QCS6490, SC8380XP, and SC8280XP-ABBB platforms
Qualcomm WCD9370/9375/9380/9385 audio codecs and WSA8830/8835/8840/8845/8845H amplifiers

Discovery Timeline

2025-07-08 - CVE-2025-27047 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-27047

Vulnerability Analysis

The vulnerability exists in the graphics driver code path that processes the TESTPATTERNCONFIG escape command. Escape paths in graphics drivers accept ioctl-style inputs from user-space clients to configure vendor-specific display behaviors such as test patterns. Improper lifetime management of a heap object referenced during this configuration flow leads to a use-after-free condition. When the driver dereferences the stale pointer, memory corruption occurs within the kernel or driver address space.

Because the driver typically runs with elevated privileges, memory corruption in this context can be steered toward arbitrary write primitives or control-flow hijack. The attack surface is exposed to any local process with permission to open the graphics device node, which on many Android and embedded platforms includes unprivileged applications.

Root Cause

The root cause is a use-after-free [CWE-416] in the TESTPATTERNCONFIG escape handler. The driver releases a heap-allocated structure while another code path retains a reference to it. Subsequent operations dereference the freed object, allowing an attacker who controls heap reallocation to substitute crafted data at the same address.

Attack Vector

Exploitation requires local access and low privileges on the target device. An attacker delivers a malicious application or process that issues a specifically crafted sequence of escape ioctls against the affected graphics driver. No user interaction is required beyond running the attacker-supplied code. The vulnerability does not require network access, limiting the initial reach but making it a strong candidate for the second stage of a mobile or embedded exploit chain following an initial application compromise.

No public proof-of-concept exploit code has been published, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2025-27047

Indicators of Compromise

Unexpected crashes, kernel panics, or driver faults referencing the graphics stack or TESTPATTERNCONFIG escape handler in device logs.
Applications without a legitimate rendering or diagnostic purpose opening the graphics device node and issuing escape ioctls.
Anomalous privilege transitions immediately following graphics driver activity from an unprivileged process.

Detection Strategies

Monitor dmesg and vendor bugreport logs for driver stack traces implicating the display or GPU escape path.
Enforce application allowlisting on managed mobile and embedded fleets to prevent execution of untrusted binaries that could reach the vulnerable ioctl surface.
Correlate telemetry from endpoint agents to identify processes issuing rare graphics escape commands paired with subsequent privilege changes.

Monitoring Recommendations

Track firmware and patch level versions across FastConnect, WCD, WSA, and Snapdragon assets to identify unpatched devices.
Ingest mobile device management (MDM) compliance events into the SIEM to alert on devices running pre-July 2025 Qualcomm patch levels.
Baseline normal graphics driver ioctl usage per application, and alert on deviations from established profiles.

How to Mitigate CVE-2025-27047

Immediate Actions Required

Apply the firmware updates referenced in the Qualcomm July 2025 Security Bulletin as delivered by the OEM or platform vendor.
Inventory devices using the affected FastConnect, QCM, QCS, SC, WCD, and WSA components, and prioritize patching for those exposed to untrusted application installation.
Restrict sideloading and enforce app store policies on managed Android and embedded devices to reduce local attacker reach.

Patch Information

Qualcomm published fixes in the July 2025 Security Bulletin. Because Qualcomm delivers patches to original equipment manufacturers (OEMs) who then integrate them into device firmware, end users must obtain updates through their device vendor's over-the-air (OTA) update channel. Verify that the Android security patch level or embedded firmware build reflects the July 2025 or later Qualcomm patch.

Workarounds

Where OEM patches are not yet available, restrict installation of untrusted applications and disable developer mode on production devices.
Apply SELinux or equivalent mandatory access control policies to limit which processes can open the affected graphics device nodes.
Isolate high-value devices on segmented networks and revoke unnecessary local user privileges until firmware updates are deployed.

bash

# Verify Android security patch level on affected devices
adb shell getprop ro.build.version.security_patch

# Confirm the value is 2025-07-01 or later before considering the device patched