CVE-2026-24080: Fingerprint TA Buffer Overflow Vulnerability

CVE-2026-24080 Overview

CVE-2026-24080 is a memory corruption vulnerability in the fingerprint Trusted Application (TA) shipped in Qualcomm components. The flaw occurs when the fingerprint TA processes malformed request parameters, leading to a buffer copy without size checking [CWE-120]. A local, authenticated attacker with low privileges can trigger the condition to compromise confidentiality, integrity, and availability of the affected component. Qualcomm disclosed the issue in the August 2026 Security Bulletin.

Critical Impact
Local exploitation of the fingerprint TA can corrupt secure world memory, potentially enabling privilege escalation into TrustZone-protected execution contexts.

Affected Products

Qualcomm chipsets exposing the fingerprint Trusted Application (see the Qualcomm Security Bulletin August 2026 for the component matrix)
Android devices integrating the affected Qualcomm fingerprint TA
OEM builds shipping vulnerable versions of the fingerprint TA firmware

Discovery Timeline

2026-08-04 - CVE-2026-24080 published to NVD
2026-08-06 - Last updated in NVD database

Technical Details for CVE-2026-24080

Vulnerability Analysis

The fingerprint TA executes inside Qualcomm's secure world and handles biometric requests forwarded from the non-secure (Android) world. The TA fails to validate the size or structure of request parameters before copying them into internal buffers. When a caller submits a malformed request, the copy operation writes outside the intended bounds, corrupting adjacent memory inside the trusted execution environment.

Because the fingerprint TA runs with high privileges inside TrustZone, memory corruption can influence the integrity of biometric matching, key handling, and secure storage operations. Qualcomm classified the issue as memory corruption under [CWE-120] (buffer copy without checking size of input).

Root Cause

The root cause is missing input validation on request parameters passed to the fingerprint TA. The TA trusts caller-supplied length or structure fields and performs a copy without enforcing bounds. This pattern is common in TA command handlers that use tagged parameter buffers.

Attack Vector

Exploitation requires local access with low privileges on the affected device. An attacker leverages a normal-world process able to issue QSEE or SMC calls to the fingerprint TA and submits a crafted parameter payload. No user interaction is required. Successful exploitation corrupts secure world memory and can escalate impact beyond the TA boundary.

No verified public exploit code or proof-of-concept is available. See the Qualcomm Security Bulletin August 2026 for vendor-supplied technical details.

Detection Methods for CVE-2026-24080

Indicators of Compromise

Unexpected crashes, resets, or kernel messages referencing the fingerprint TA or qseecom interface
Untrusted or sideloaded applications issuing repeated ioctl requests to /dev/qseecom
Anomalous biometric authentication failures preceding device instability

Detection Strategies

Monitor mobile device management (MDM) telemetry for devices running Qualcomm firmware predating the August 2026 patch level
Inspect logs from Android's keystore and biometric subsystems for repeated malformed request errors returned by the fingerprint TA
Alert on installation of applications that request access to low-level device interfaces without a legitimate business need

Monitoring Recommendations

Track the Android security patch level across the mobile fleet and flag devices missing the August 2026 Qualcomm updates
Correlate biometric subsystem errors with process execution telemetry to identify local exploitation attempts
Review Qualcomm advisories monthly to maintain coverage of TrustZone and TA vulnerabilities

How to Mitigate CVE-2026-24080

Immediate Actions Required

Apply the August 2026 Qualcomm firmware update as soon as OEM builds become available
Enforce a minimum Android security patch level policy through MDM to block non-compliant devices from sensitive resources
Restrict sideloading and unknown-source application installation on managed devices

Patch Information

Qualcomm published fixes in the Qualcomm Security Bulletin August 2026. Device OEMs must integrate the patched fingerprint TA firmware into their monthly Android security updates. End users should install vendor updates as soon as they are offered.

Workarounds

Disable fingerprint authentication on affected devices until firmware updates are installed, falling back to PIN or password unlock
Limit local access by enforcing full-disk encryption, screen lock timeouts, and application allowlists
Segment high-risk mobile devices from sensitive corporate resources until they reach the required patch level

bash

# Verify Android security patch level on a managed device via ADB
adb shell getprop ro.build.version.security_patch

# Expected output should be 2026-08-01 or later once the fix is applied