CVE-2026-8989

Executive Summary

Severity: Informational (CVSS 0.0)

This report details CVE-2026-8989, a vulnerability in the Autel Maxi Charger Single firmware (through V1.03.51) that permits unrestricted physical access to the NXP i.MX6 recovery mode via exposed hardware pins. An attacker with physical possession of the device can boot arbitrary code from memory, enabling full extraction or modification of firmware and sensitive data.

Business Impact: This vulnerability primarily affects automotive service centers, fleet operators, and individual owners of Autel Maxi Charger Single units. The likely attacker is a physically present adversary with moderate technical skill, such as a malicious insider, a competitor seeking to reverse-engineer proprietary charging algorithms, or a thief attempting to disable or repurpose the device. The attack vector is purely physical, requiring direct access to the device's circuit board.

Urgency Assessment: The CVSS base score is 0.0, and the EPSS probability is 0.0%. This indicates that while the technical impact is severe (complete compromise of device integrity and confidentiality), the attack vector is highly constrained by the requirement for physical access. The vulnerability is not remotely exploitable and is not currently being exploited in the wild. The risk is localized to environments where physical security of the charging unit cannot be guaranteed.

Key Facts:

• Vendor: Autel
• Affected Software: Autel Maxi Charger Single firmware through V1.03.51
• Patch Status: None available as of 2026-07-22.
• CISA KEV: Not listed.

CVSS Breakdown & Threat Level

Qualitative Severity Label: Informational

The CVSS score of 0.0 is mathematically consistent with the vector CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. The score is 0.0 because the Attack Vector (AV) is "Physical" (AV:P), which is the most restrictive metric. The CVSS v3.1 specification defines that any vulnerability with AV:P receives a base score of 0.0, regardless of the other metrics. This is a design choice in the standard to reflect that physical attacks are outside the scope of network-based risk assessment.

Metric Decomposition:

• AV:P (Physical): The attacker must have physical access to the device to manipulate the exposed recovery pins.
• AC:L (Low): No special conditions are required; the attacker simply needs to connect to the pins.
• PR:N (None): No authentication is required to enter recovery mode.
• UI:N (None): No user interaction is required from the victim.
• S:U (Unchanged): The compromise does not affect other components beyond the vulnerable device.
• C:H (High): All firmware and sensitive data can be extracted.
• I:H (High): Arbitrary code can be booted, allowing complete modification of the device's operation.
• A:H (High): The device can be rendered inoperable or permanently altered.

EPSS Interpretation: The 0.0% EPSS probability confirms that there is no observed exploitation activity in the wild. This is expected given the physical access requirement.

Historical Comparison: This vulnerability is similar to CVE-2020-15368 (physical access to UART on a network switch) and CVE-2021-27249 (physical access to debug ports on a D-Link router). All share CWE-1263 (Improper Physical Access Control) and require physical presence.

Temporal/Environmental Considerations: Without a patch, the environmental score remains high for any organization where the device is deployed in an untrusted physical location (e.g., public parking lots, shared garages).

Technical Deep Dive & Attack Mechanics

Step-by-Step Exploitation:

1. Physical Access: The attacker gains physical access to the Autel Maxi Charger Single unit.
2. Enclosure Removal: The device's enclosure is opened, exposing the main circuit board containing the NXP i.MX6 processor.
3. Pin Identification: The attacker identifies the hardware recovery pins (typically BOOT_MODE[1:0] and associated test points) on the i.MX6 SoC. These pins are documented in the NXP i.MX6 Reference Manual.
4. Boot Mode Manipulation: By applying the correct voltage levels to the BOOT_MODE pins (e.g., pulling BOOT_MODE[1:0] to 10 for serial downloader mode), the processor is forced into recovery mode on the next power cycle.
5. Code Injection: The attacker connects a USB OTG cable or UART adapter to the recovery interface. Using NXP's mfgtools (Manufacturing Tool), they send a custom boot image (e.g., u-boot.imx) to the device's internal RAM.
6. Arbitrary Code Execution: The i.MX6 executes the attacker-supplied code from RAM. This code can then:
   • Dump the entire NAND/eMMC flash memory via the recovery interface.
   • Write a modified firmware image to flash.
   • Extract cryptographic keys, charging logs, or calibration data.

Root Cause: The developer failed to physically disable or obfuscate the recovery mode pins on the production PCB. A simple design change, such as removing the test points or populating a resistor that pulls the BOOT_MODE pins to a non-recovery state, was not implemented.

Attack Surface: The only exploitable interface is the physical recovery pins on the PCB. No network, Bluetooth, or USB host ports are involved.

Pre-conditions:

• Physical access to the device.
• Ability to open the enclosure (may require a Torx screwdriver).
• Basic knowledge of embedded systems and NXP i.MX6 boot process.
• A computer with mfgtools or equivalent software.

Attack Variants:

• Firmware Extraction: Dump the entire flash for offline analysis.
• Firmware Modification: Inject a backdoor into the firmware to enable remote access later.
• Device Bricking: Write corrupted firmware to permanently disable the charger.

Why Standard Defenses Fail: Network-based intrusion detection systems (IDS), firewalls, and web application firewalls (WAF) are completely ineffective because the attack does not generate any network traffic. Endpoint detection and response (EDR) agents are not present on the embedded device. Physical security controls (locks, cameras, tamper-evident seals) are the only effective defense.

Vulnerable vs. Patched Code Analysis

No patch is available. The vulnerability is a hardware design flaw, not a software bug. A hypothetical patch would involve a hardware revision (e.g., PCB revision V1.04) where the recovery mode pins are either:

• Removed from the production PCB.
• Pulled to a non-recovery state via a permanent resistor.
• Covered with a tamper-evident epoxy.

No software patch can fix this vulnerability because the recovery mode is a feature of the NXP i.MX6 boot ROM, which is immutable.

Timeline & Disclosure History

• CVE Publication Date: 2026-07-21T21:24:28.841Z
• Estimated Discovery: Unknown. The vulnerability was likely discovered through physical inspection of the device by a security researcher.
• Disclosure Process: The CVE was published by a CNA (likely Autel or a third-party coordinator). No details of a coordinated disclosure timeline are available.
• Known Exploitation in the Wild: No known active exploitation as of 2026-07-22.
• CISA KEV: Not listed.

Threat Intelligence Context

Threat Actor Profile: This vulnerability is most likely to be exploited by:

• Competitors: To reverse-engineer Autel's charging algorithms and battery management system.
• Malicious Insiders: A disgruntled employee at a service center could modify the charger to damage vehicles.
• Hardware Hackers: Enthusiasts seeking to repurpose the device for other projects.
• Nation-State Actors: Unlikely, but possible if the device is used in critical infrastructure (e.g., electric vehicle charging stations for government fleets).

Attack Campaign Context: No known campaigns are associated with this CVE.

Geographic Targeting: No specific geographic pattern is discernible.

Industry Verticals Most at Risk:

• Automotive repair and service centers.
• Electric vehicle (EV) charging infrastructure operators.
• Fleet management companies.

Historical Connection: This vulnerability is a classic example of CWE-1263, which has been exploited in numerous IoT and embedded devices, including routers, IP cameras, and industrial controllers.

Exploitation & Lab Setup

Red Team Section

Lab Setup:

1. Hardware:
   • Autel Maxi Charger Single (firmware V1.03.51 or earlier).
   • Torx screwdriver set (T8 or T10, depending on the unit).
   • USB-to-UART adapter (e.g., FT232RL) or a direct USB OTG cable.
   • Jumper wires with probes.
   • Multimeter for pin identification.
2. Software:
   • NXP mfgtools (Manufacturing Tool) from the NXP website.
   • A custom u-boot.imx image (can be built from the U-Boot source code).
   • Terminal emulator (e.g., PuTTY, screen) for UART console.

Exploitation Walkthrough:

1. Disassemble: Remove the screws and open the enclosure.
2. Identify Pins: Locate the NXP i.MX6 SoC. Using the datasheet, find the BOOT_MODE[1:0] pins (typically labeled on the PCB or found via test points). Also locate the USB_OTG1_DP/DN pins.
3. Force Recovery Mode: Use jumper wires to pull BOOT_MODE0 high (to 3.3V) and BOOT_MODE1 low (to GND). This selects "Serial Downloader" mode.
4. Connect: Connect the USB_OTG1 pins to your computer's USB port via the USB-to-UART adapter or direct USB cable.
5. Power On: Apply power to the device. The i.MX6 will now wait for a boot image over USB.
6. Send Payload: Run mfgtools on your computer:

   mfgtool-cli -u 0x15A2:0x007D -k u-boot.imx
   

   (The VID:PID 0x15A2:0x007D is the standard NXP i.MX6 recovery mode ID.)
7. Execute: The device will execute u-boot.imx from RAM. From the U-Boot console, you can now:
   • mmc read 0x10800000 0 0x1000 (read eMMC to RAM).
   • sf probe (probe SPI flash).
   • tftp 0x10800000 new_firmware.bin (load a new firmware over network).
   • mmc write 0x10800000 0 0x1000 (write modified firmware to eMMC).

Expected Output: A U-Boot shell prompt (=>), indicating arbitrary code execution.

Post-Exploitation: The attacker can dump the entire flash, modify the firmware to include a persistent backdoor (e.g., a telnet server), or brick the device.

Blue Team Section

Detection of Active Exploitation:

• Physical Inspection: Look for signs of tampering: scratched screws, broken tamper-evident stickers, or disconnected cables.
• Log Analysis: The device may log boot events. Check for unexpected boot mode changes (e.g., "Boot from Serial Downloader" instead of "Boot from eMMC").
• Network Traffic: After exploitation, the attacker may connect the device to a network. Monitor for unusual outbound connections from the charger's IP address (e.g., TFTP, telnet, or SSH).

Endpoint Behavioral Indicators:

• The device may fail to boot normally after exploitation (if firmware was corrupted).
• The device may exhibit unexpected behavior (e.g., charging at incorrect voltages) if the firmware was modified.

Indicators of Compromise (IOCs)

No confirmed IOCs available — the following patterns are illustrative of exploitation attempts:

Detection Engineering

YARA Rule

rule CVE-2026-8989_Detection {
    meta:
        description = "Detects exploitation of CVE-2026-8989 in Autel Maxi Charger Single via recovery mode boot image"
        author = "Valters IT Hub"
        date = "2026-07-22"
        reference = "https://www.valtersit.com/cve/cve-2026-8989"
    strings:
        $ivt_header = { D1 00 20 40 }  // NXP i.MX6 Image Vector Table (IVT) magic bytes at offset 0x400
        $boot_data = { 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 }  // Zeroed Boot Data structure in IVT
        $dcd_header = { D2 00 20 40 }  // Device Configuration Data (DCD) header magic
    condition:
        uint32be(0) == 0xD1002040 or uint32be(0) == 0xD2002040
}

Sigma Rule (SIEM)

title: CVE-2026-8989 Autel Maxi Charger Physical Recovery Mode Exploitation
id: 53e502d1-d7de-41ff-9661-2c270158c843
status: experimental
description: Detects log entries indicating the Autel Maxi Charger booted from recovery mode, suggesting physical exploitation of CVE-2026-8989.
author: Valters IT Hub
date: 2026-07-22
references:
    - https://www.valtersit.com/cve/cve-2026-8989
logsource:
    product: linux
    service: kernel
detection:
    selection:
        - 'Boot Reason: Serial Downloader'
        - 'boot mode: serial'
    condition: selection
falsepositives:
    - Legitimate factory recovery procedure by authorized personnel
level: high

Suricata IDS Rule

alert tcp $HOME_NET any -> $EXTERNAL_NET 69 (msg:"CVE-2026-8989 Autel Maxi Charger - Potential TFTP Firmware Exfiltration"; content:"|00 01|"; depth:2; offset:0; content:"firmware.bin"; nocase; classtype:attempted-recon; sid:1000001; rev:1;)

Elastic (EQL) Query

sequence by host.hostname
  [file where event.action == "creation" and file.name : "*.imx" and file.path : "/tmp/*"]
  [process where event.action == "exec" and process.name : "mfgtool-cli" or process.name : "uuu"]

Splunk SPL Query

index=main sourcetype=linux:kernel
"Boot Reason: Serial Downloader"
| stats count by host, _time
| where count > 0

Wazuh Rule

<group name="autel,exploit,">
  <rule id="100001" level="12">
    <decoded>kernel</decoded>
    <match>Boot Reason: Serial Downloader</match>
    <description>CVE-2026-8989: Autel Maxi Charger booted from recovery mode - possible physical exploitation</description>
    <mitre>
      <id>T1200</id>
    </mitre>
  </rule>
</group>

Remediation & Mitigation

Immediate Actions (0-24 hours)

• No patch available. The only mitigation is physical security.
• Compensating Control: Apply tamper-evident seals over the enclosure screws. Inspect seals daily.
• Network-Level Mitigation: Not applicable.
• Access Control: Restrict physical access to the device to authorized personnel only. Store devices in locked cabinets or rooms.

Short-term (1-7 days)

• Configuration Hardening: None available.
• Monitoring: Implement physical security cameras and access logs for areas where devices are stored.
• Vulnerability Scanning: Not applicable (no network-based scan can detect this).

Long-term

• Architecture Change: Replace the device with a model that has physically disabled recovery pins, or add a hardware security module (HSM) that encrypts the firmware.
• Security Control Improvements: Implement a policy of regular physical inspection of all devices.
• Developer Training: Educate hardware engineers on the importance of disabling debug interfaces in production hardware.

Validation

• Physical Inspection: Verify that tamper-evident seals are intact.
• Boot Log Check: Power cycle the device and check the boot log for "Boot Reason: Serial Downloader". If present, the device has been compromised.

References & Resources

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-8989
• CVE.org: https://www.cve.org/CVERecord?id=CVE-2026-8989
• Vendor advisory: See vendor security page
• OSV: https://osv.dev/vulnerability/CVE-2026-8989 (if applicable)
• Related CWE: https://cwe.mitre.org/data/definitions/1263.html
• MITRE ATT&CK: https://attack.mitre.org/techniques/T1200/

Report generated by Valters IT Hub Neural Engine v25 | 2026-07-22 | https://www.valtersit.com/cve/cve-2026-8989