CVE-2026-6840: Buffer Overflow Vulnerability in ML Model

CVE-2026-6840 Overview

CVE-2026-6840 is an input validation vulnerability affecting Samsung ONE (On-device Neural Engine), an open-source neural network compiler and runtime framework. The vulnerability stems from missing bounds validation for operator codes during model loading, which could allow an out-of-range operator-code lookup, potentially leading to denial of service conditions.

Critical Impact

A local attacker could craft a malicious model file that triggers an out-of-bounds memory access during model loading, causing application crashes and denial of service.

Affected Products

• Samsung ONE (On-device Neural Engine) versions prior to commit 1.30.0

Discovery Timeline

• 2026-04-22 - CVE CVE-2026-6840 published to NVD
• 2026-04-22 - Last updated in NVD database

Technical Details for CVE-2026-6840

Vulnerability Analysis

This vulnerability is classified under CWE-129 (Improper Validation of Array Index), indicating that the affected code fails to properly validate array index values before using them to access memory. In the context of Samsung ONE, when loading a neural network model, the framework processes operator codes that determine which operations to execute. Without proper bounds checking, an attacker-controlled model file can specify an operator code value that exceeds the valid range of the operator lookup table.

The attack requires local access and user interaction (such as opening a malicious model file), but does not require elevated privileges. The primary impact is on availability, as successful exploitation leads to application crashes through memory access violations. There is no direct impact on data confidentiality or integrity.

Root Cause

The root cause is the absence of bounds validation when processing operator codes from model files. During the model loading phase, operator codes are used as indices to look up corresponding operation handlers. When these indices are not validated against the bounds of the operator table, out-of-range values can cause memory access violations. This is a classic CWE-129 scenario where untrusted input is used directly as an array index without validation.

Attack Vector

The attack vector requires local access to the target system. An attacker would need to craft a malicious model file containing an invalid operator code value that falls outside the expected range. When a user or application attempts to load this malicious model using Samsung ONE, the framework attempts to look up the invalid operator code, resulting in an out-of-bounds memory access that crashes the application.

The exploitation scenario involves:

1. Attacker creates a specially crafted model file with an out-of-range operator code
2. Victim obtains the malicious model file (via download, email attachment, etc.)
3. Victim's application attempts to load the model using Samsung ONE
4. The invalid operator code triggers an out-of-bounds lookup
5. Application crashes due to memory access violation

For technical implementation details of the fix, refer to the GitHub Pull Request for ONE.

Detection Methods for CVE-2026-6840

Indicators of Compromise

• Application crashes when loading neural network model files from untrusted sources
• Unexpected process termination events associated with Samsung ONE-based applications
• Memory access violation errors in system logs during model loading operations

Detection Strategies

• Monitor for abnormal application termination events in processes using Samsung ONE libraries
• Implement file integrity monitoring for model files in production environments
• Enable crash dump collection to analyze potential exploitation attempts
• Review application logs for model loading failures or exceptions

Monitoring Recommendations

• Configure application crash reporting to capture and analyze model loading failures
• Implement anomaly detection for unusual patterns in model file access
• Set up alerting for repeated crashes in applications utilizing Samsung ONE
• Monitor system event logs for memory access violation events

How to Mitigate CVE-2026-6840

Immediate Actions Required

• Update Samsung ONE to version 1.30.0 or later to obtain the security fix
• Restrict model file loading to trusted sources only until patches are applied
• Implement application-level sandboxing to limit the impact of potential crashes
• Review and audit any custom model files for integrity before deployment

Patch Information

Samsung has addressed this vulnerability through a code update available in the GitHub Pull Request for ONE. The fix implements proper bounds validation for operator codes during model loading, preventing out-of-range lookups. Organizations using Samsung ONE should update to version 1.30.0 or apply the patch from the referenced pull request.

Workarounds

• Validate model files before loading by implementing pre-load integrity checks
• Load model files only from trusted and verified sources
• Run applications using Samsung ONE in sandboxed or containerized environments to contain potential crashes
• Implement application-level exception handling to gracefully manage model loading failures

Organizations should apply the official patch as soon as possible, as workarounds only provide partial protection and do not address the underlying vulnerability.