CVE-2025-21442: Qualcomm QAM8255P Buffer Overflow Flaw

CVE-2025-21442 Overview

CVE-2025-21442 is a memory corruption vulnerability affecting a wide range of Qualcomm automotive and connectivity chipsets. The flaw occurs when the affected firmware transmits packet mapping information containing an invalid header payload size. Qualcomm addressed the issue in the Qualcomm April 2025 Security Bulletin. The weakness is classified under [CWE-680] (Integer Overflow to Buffer Overflow). Successful exploitation requires local access with low privileges and no user interaction, and can compromise confidentiality, integrity, and availability of the affected component.

Critical Impact
A local, low-privileged attacker can trigger memory corruption in Qualcomm firmware by supplying a crafted header payload size, potentially leading to arbitrary code execution within the affected component.

Affected Products

Qualcomm automotive platforms including SA8255P, SA8295P, SA8540P, SA8620P, SA8650P, SA8770P, SA8775P, SA9000P, SA7255P, and SA7775P firmware
Qualcomm QAM-series platforms including QAM8255P, QAM8295P, QAM8620P, QAM8650P, QAM8775P, QAMSRV1H, and QAMSRV1M firmware
Qualcomm connectivity and server chipsets including QCA6574AU, QCA6595, QCA6595AU, QCA6688AQ, QCA6696, QCA6698AQ, SRV1H, SRV1L, and SRV1M firmware

Discovery Timeline

2025-04-07 - CVE-2025-21442 published to NVD alongside Qualcomm's April 2025 Security Bulletin
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-21442

Vulnerability Analysis

The vulnerability resides in Qualcomm firmware logic that transmits packet mapping information. When constructing or forwarding a packet, the affected code path accepts a header payload size value without adequate validation. An invalid or attacker-controlled size drives downstream memory operations such as buffer allocation, indexing, or copying beyond intended bounds. The result is memory corruption inside the firmware component that processes the packet metadata.

Because the impacted components run within trusted firmware on Qualcomm system-on-chip (SoC) platforms used in automotive, connectivity, and infotainment systems, memory corruption at this layer can lead to code execution at a privilege level below the operating system. Exploitation compromises confidentiality, integrity, and availability of the affected component.

Root Cause

The flaw is mapped to [CWE-680], an integer wraparound that reaches a buffer allocation or copy operation. The header payload size field is trusted rather than sanity-checked against the actual buffer or protocol constraints. When the size crosses arithmetic boundaries, the ensuing allocation is undersized relative to the data copied, producing a buffer overflow condition.

Attack Vector

Exploitation requires local access to the target device with low privileges and no user interaction. An attacker with the ability to invoke the vulnerable packet mapping interface, typically through a user-space process communicating with the firmware, submits crafted packet metadata containing a malformed header payload size. See the Qualcomm April 2025 Security Bulletin for component-level details.

No public proof-of-concept, exploit database entry, or in-the-wild exploitation has been reported for CVE-2025-21442 at the time of writing.

Detection Methods for CVE-2025-21442

Indicators of Compromise

Unexpected firmware crashes, watchdog resets, or subsystem restarts on Qualcomm automotive or connectivity chipsets
Kernel log entries referencing packet mapping or transport driver faults that correlate with abnormal payload sizes
Local processes with unusual access patterns to Qualcomm driver interfaces exposed through /dev nodes or ioctl endpoints

Detection Strategies

Monitor firmware and kernel telemetry for repeated faults in Qualcomm subsystem drivers that handle packet mapping
Correlate userspace process activity with driver-level faults to identify local privilege boundary crossings
Track installed firmware and baseband versions against the fixed builds referenced in Qualcomm's April 2025 bulletin

Monitoring Recommendations

Ingest device and kernel logs into a centralized analytics platform to detect anomalous firmware crash patterns across fleets
Alert on processes attempting undocumented ioctl or shared memory operations against Qualcomm driver endpoints
Establish a baseline of expected firmware versions for each SoC model and flag deviations

How to Mitigate CVE-2025-21442

Immediate Actions Required

Apply the firmware updates provided by Qualcomm and downstream OEMs referenced in the April 2025 Security Bulletin
Inventory automotive, IoT, and connectivity devices using the affected QAM, QCA, SA, and SRV chipsets
Restrict local access to devices that cannot yet be patched, including physical, debug, and diagnostic interfaces
Enforce least-privilege on user-space processes that can communicate with Qualcomm firmware components

Patch Information

Qualcomm has released fixes for the affected chipsets in the April 2025 Security Bulletin. OEMs and integrators must incorporate the updated firmware into their board support packages and distribute them through their standard update channels. Refer to the Qualcomm April 2025 Security Bulletin for the authoritative list of fixed builds per component.

Workarounds

Limit which local accounts and processes can access Qualcomm driver interfaces on multi-user or multi-tenant devices
Disable optional connectivity or telematics features that rely on the affected packet mapping paths where operationally acceptable
Deploy endpoint policies that block unsigned or unapproved binaries from executing on the host operating system running above the firmware

bash

# Configuration example: restrict access to Qualcomm driver interfaces on Linux-based systems
sudo chown root:qcom-priv /dev/qcom_*
sudo chmod 660 /dev/qcom_*
sudo usermod -aG qcom-priv <trusted_service_account>