CVE-2026-2541: Micca KE700 Auth Bypass Vulnerability

CVE-2026-2541 Overview

The Micca KE700 system contains a critical cryptographic vulnerability stemming from insufficient entropy in its rolling code authentication mechanism. The system relies on only a 6-bit portion of an identifier for authentication within rolling codes, providing a mere 64 possible combinations. This low entropy design flaw allows an attacker within adjacent network range to perform a brute-force attack against one component of the rolling code. Successful exploitation enables an attacker to predict the next valid rolling code, potentially granting unauthorized access to the vehicle.

Critical Impact

An attacker within adjacent network range can brute-force the 6-bit authentication identifier (64 combinations) to predict valid rolling codes and gain unauthorized vehicle access.

Affected Products

• Micca KE700 System

Discovery Timeline

• 2026-02-15 - CVE CVE-2026-2541 published to NVD
• 2026-02-18 - Last updated in NVD database

Technical Details for CVE-2026-2541

Vulnerability Analysis

This vulnerability is classified under CWE-331 (Insufficient Entropy), which describes a condition where the random values or other data lack sufficient unpredictability to resist cryptographic attacks. In the context of the Micca KE700 vehicle access system, the rolling code mechanism—designed to prevent replay attacks—has been fundamentally undermined by the use of an inadequately small key space.

Rolling codes are a standard security mechanism in automotive keyless entry systems where each button press generates a new code from a cryptographic sequence. When properly implemented, rolling codes provide strong protection against replay attacks. However, the Micca KE700's implementation uses only 6 bits for a critical authentication identifier component, creating a key space of only 64 unique values.

From an exploitation standpoint, an attacker positioned within adjacent network proximity can systematically iterate through all 64 possible combinations in minimal time. Once the correct identifier is discovered, the attacker can synchronize with the rolling code sequence and predict subsequent valid codes, effectively bypassing the authentication mechanism entirely.

Root Cause

The root cause of this vulnerability lies in a fundamental design flaw in the Micca KE700's rolling code implementation. The selection of a 6-bit field for the authentication identifier component is cryptographically insufficient. Industry best practices for rolling code systems typically require significantly larger key spaces (commonly 40-bit or greater) to resist brute-force attacks. The choice of 6 bits represents a severe departure from established cryptographic standards, providing only 2^6 = 64 possible values—a number that can be exhaustively searched in seconds.

Attack Vector

The attack requires adjacent network proximity to the target vehicle, meaning the attacker must be within RF communication range of the Micca KE700 system. The attack sequence involves:

1. Signal Interception: The attacker monitors RF communications between the key fob and the vehicle to capture rolling code transmissions.

2. Brute-Force Enumeration: Using captured data, the attacker systematically tests all 64 possible values for the 6-bit identifier component.

3. Sequence Prediction: Once the correct identifier is determined, the attacker can predict subsequent rolling codes in the sequence.

4. Unauthorized Access: The attacker transmits the predicted rolling code to unlock the vehicle or gain other unauthorized access.

The attack does not require user interaction, prior authentication, or special privileges. The primary limitation is the physical proximity requirement inherent to the adjacent network attack vector. For detailed technical information, refer to the ASRG Security Advisory.

Detection Methods for CVE-2026-2541

Indicators of Compromise

• Unusual or repeated RF signal transmissions near the vehicle that deviate from normal key fob usage patterns
• Multiple failed authentication attempts in quick succession followed by successful access
• Evidence of RF jamming or signal manipulation in proximity to the vehicle
• Unexpected vehicle access events when legitimate key fobs are not in range

Detection Strategies

• Deploy RF spectrum monitoring solutions capable of detecting anomalous wireless activity near protected vehicles
• Implement logging mechanisms on vehicle access systems to capture and analyze authentication event patterns
• Configure alerts for rapid sequential authentication attempts that may indicate brute-force activity
• Review access logs for temporal anomalies such as access events during unusual hours

Monitoring Recommendations

• Establish baseline RF activity patterns around vehicles to identify deviations indicative of attack activity
• Integrate vehicle access logs with centralized security monitoring platforms where possible
• Conduct periodic security assessments of wireless communication protocols in use
• Monitor for public disclosures of exploit tools or techniques targeting Micca KE700 systems

How to Mitigate CVE-2026-2541

Immediate Actions Required

• Contact Micca support or your vehicle manufacturer to inquire about firmware updates or security patches addressing this vulnerability
• Consider supplementary physical security measures such as steering wheel locks or kill switches
• Be vigilant about RF interference or unusual electronic behavior near your vehicle
• Avoid relying solely on the Micca KE700 system for vehicle security until a fix is available

Patch Information

No vendor patch information is currently available in the CVE data. Organizations and individuals using the Micca KE700 system should monitor the ASRG Security Advisory for updates regarding remediation options and vendor response.

Workarounds

• Implement additional layers of physical security to protect the vehicle independent of the electronic access system
• Where possible, disable or supplement the Micca KE700 with alternative authentication mechanisms
• Consider RF shielding solutions for key fobs when not in use to prevent signal interception
• Maintain awareness of vehicle surroundings and report suspicious electronic interference to security personnel

Due to the hardware-level nature of this vulnerability (insufficient entropy in the rolling code design), software-based configuration changes may not fully mitigate the risk. Hardware replacement or manufacturer-provided updates may ultimately be required for complete remediation.