CVE-2026-25290: Memory Corruption Buffer Overflow Vulnerability

CVE-2026-25290 Overview

CVE-2026-25290 is a memory corruption vulnerability that occurs when validating large data buffers received from external sources. The flaw stems from using addition to compute buffer length checks, which can overflow and produce a smaller value than expected. The affected code then trusts the truncated result and processes attacker-supplied data beyond the intended bounds. The issue is categorized under [CWE-190] Integer Overflow or Wraparound and was disclosed in the Qualcomm September 2026 Security Bulletin.

Critical Impact
A local, low-privileged attacker supplying crafted input can trigger memory corruption leading to code execution or full compromise of confidentiality, integrity, and availability on the affected component.

Affected Products

Qualcomm components referenced in the September 2026 Security Bulletin
Specific chipset and driver versions listed by the vendor advisory
Downstream OEM firmware integrating the affected Qualcomm components

Discovery Timeline

2026-09-17 - CVE-2026-25290 published to NVD
2026-09-17 - Last updated in NVD database
September 2026 - Disclosed in the Qualcomm September 2026 Security Bulletin

Technical Details for CVE-2026-25290

Vulnerability Analysis

The vulnerability resides in input validation logic that checks whether a data buffer fits within an allocated region. The code adds an offset and a length value, then compares the sum against a maximum size. When the two operands are large, the addition wraps around the fixed-width integer type and yields a small result. The bounds check passes even though the true combined size exceeds the allocation. Subsequent read or write operations then overrun the buffer, corrupting adjacent memory structures.

Exploitation requires local access with low privileges and no user interaction. Successful triggering can lead to arbitrary code execution in the context of the vulnerable component, which on mobile and embedded Qualcomm platforms often runs with elevated privileges.

Root Cause

The root cause is an unchecked arithmetic operation in a length-validation routine. The developer used a pattern such as if (offset + length > buffer_size) without first verifying that neither operand nor their sum could exceed the range of the integer type. This is a canonical [CWE-190] Integer Overflow or Wraparound weakness. Safe alternatives include comparing operands independently, using checked arithmetic intrinsics, or promoting values to a wider integer type before summation.

Attack Vector

An attacker with local access supplies a crafted data buffer through an interface that reaches the vulnerable component, such as an ioctl, shared memory region, or IPC channel exposed to unprivileged processes. The malicious input specifies offset and length fields chosen so that their sum wraps to a value below the buffer size. The validation routine accepts the request, and the subsequent memory operation writes or reads outside the allocation, producing memory corruption that can be shaped into code execution.

No verified public exploit code is available. Refer to the Qualcomm September 2026 Security Bulletin for component-specific technical details.

Detection Methods for CVE-2026-25290

Indicators of Compromise

Unexpected crashes, kernel panics, or SIGSEGV events originating from the affected Qualcomm driver or service
Anomalous ioctl or IPC requests carrying oversized length or offset fields to Qualcomm kernel interfaces
Local processes with low privileges spawning unexpected child processes after interacting with the vulnerable component

Detection Strategies

Deploy behavioral endpoint monitoring that flags memory corruption patterns and post-exploitation activity following interaction with kernel-mode drivers.
Enable kernel address sanitizer (KASAN) or equivalent instrumentation in test builds to catch out-of-bounds accesses triggered by fuzzed input.
Correlate crash telemetry with process lineage to identify unprivileged processes triggering repeated faults in Qualcomm components.

Monitoring Recommendations

Collect and centralize crash dumps and kernel logs from mobile and embedded fleets for anomaly analysis.
Alert on privilege transitions where a low-privileged process gains elevated capabilities shortly after driver interaction.
Baseline normal ioctl usage patterns for Qualcomm interfaces and alert on deviations in request size or frequency.

How to Mitigate CVE-2026-25290

Immediate Actions Required

Inventory devices running affected Qualcomm chipsets and identify OEM firmware versions in use.
Apply the September 2026 Qualcomm security patch as soon as it is available through your device or platform vendor.
Restrict local access to affected interfaces where feasible until patches are deployed.

Patch Information

Qualcomm released fixes as part of the September 2026 Security Bulletin. OEMs integrate these fixes into device firmware updates. Consult the Qualcomm September 2026 Security Bulletin for the list of affected components and corresponding patch identifiers, then track the corresponding OEM firmware release for your deployed devices.

Workarounds

Limit installation of untrusted applications on affected devices to reduce local attacker access.
Enforce mobile device management policies that block sideloading and restrict developer options.
Where supported, disable or restrict access to the specific Qualcomm interfaces identified in the vendor advisory until firmware updates are applied.

bash

# Example: verify patch level on Android devices
adb shell getprop ro.build.version.security_patch
# Confirm value is 2026-09-01 or later per OEM guidance