USN-8963-1: NVIDIA Tegra Linux Kernel Race Conditions and Null Dereference — Detection and Patch Strategy

---
title: Linux Kernel Module Load Activity
id: 9f8e7d6c-5b4a-4c3d-2e1f-0a9b8c7d6e5f
status: experimental
description: Detects loading of kernel modules, which may indicate preparation for exploitation or rootkit installation.
references:
  - https://ubuntu.com/security/notices/USN-8963-1
author: Security Arsenal
date: 2026/04/06
tags:
  - attack.persistence
  - attack.t1547.006
logsource:
  product: linux
  category: process_creation
detection:
  selection:
    CommandLine|contains:
      - 'insmod'
      - 'modprobe'
      - 'rmmod'
  filter:
    User: 'root'
  condition: selection and not filter
falsepositives:
  - Legitimate system administration
  - Automated hardware configuration
level: medium
---
title: AX.25 Protocol Interface Activity
id: 1a2b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects creation or configuration of AX.25 network interfaces, which are rare in enterprise environments and may indicate exploitation of CVE-2022-1205.
references:
  - https://ubuntu.com/security/notices/USN-8963-1
author: Security Arsenal
date: 2026/04/06
tags:
  - attack.discovery
  - attack.t1046
logsource:
  product: linux
  category: process_creation
detection:
  selection:
    CommandLine|contains:
      - 'ax25'
      - 'kissattach'
      - 'mkiss'
falsepositives:
  - Amateur radio operators
  - Legacy industrial control systems
level: low
---
title: Kernel Panic or Crash Indicators
id: 7c8d9e0f-1a2b-3c4d-5e6f-7a8b9c0d1e2f
status: experimental
description: Detects kernel panic or crash messages in system logs, which may result from successful exploitation of CVE-2022-1205 or CVE-2022-3114.
references:
  - https://ubuntu.com/security/notices/USN-8963-1
author: Security Arsenal
date: 2026/04/06
tags:
  - attack.impact
  - attack.t1499
logsource:
  product: linux
  service: syslog
detection:
  selection:
    Message|contains:
      - 'Kernel panic'
      - 'Oops:'
      - 'BUG:'
      - 'Unable to handle kernel NULL pointer dereference'
falsepositives:
  - Hardware failures
  - Unrelated kernel bugs
level: high

// Hunt for Kernel Crash Events and Suspicious Module Loads on Linux
union isfuzzy=true
(
    Syslog
    | where Facility == "kern"
    | where SeverityLevel in ("emerg", "alert", "crit")
    | where SyslogMessage has_any ("Kernel panic", "Oops:", "BUG:", "Unable to handle kernel NULL pointer dereference")
    | extend Indicator = "Kernel Crash"
),
(
    Syslog
    | where ProcessName in ("insmod", "modprobe", "rmmod")
    | where SyslogMessage has_any ("ax25", "clk-imx")
    | extend Indicator = "Suspicious Module Load"
)
| project TimeGenerated, Computer, Indicator, ProcessName, SyslogMessage, SeverityLevel
| order by TimeGenerated desc

-- Hunt for Tegra Kernel Exploitation Artifacts
SELECT 
    Pid, 
    Name, 
    CommandLine, 
    Exe, 
    Username
FROM pslist()
WHERE CommandLine =~ 'insmod|modprobe'
   OR CommandLine =~ 'ax25|kissattach|mkiss'

-- Check for loaded AX.25 and i.MX clock modules
SELECT 
    Name, 
    Size, 
    UsedBy
FROM lsmod()
WHERE Name =~ 'ax25|clk-imx'

-- Hunt for kernel panic logs
SELECT 
    Timestamp,
    Message
FROM glob(globs='/var/log/kern.log*')
WHERE Message =~ 'Kernel panic|Oops|BUG:|NULL pointer dereference'
ORDER BY Timestamp DESC
LIMIT 100

#!/bin/bash
# USN-8963-1 Remediation Script for NVIDIA Tegra Systems

# Check if running on NVIDIA Tegra
if ! grep -q "Tegra" /proc/device-tree/model 2>/dev/null; then
    echo "[!] This system does not appear to be NVIDIA Tegra. Exiting."
    exit 0
fi

echo "[*] Detected NVIDIA Tegra system. Checking kernel version..."

# Get current kernel version
KERNEL_VERSION=$(uname -r)
echo "[*] Current Kernel: $KERNEL_VERSION"

# Check for AX.25 and i.MX modules
if lsmod | grep -q "ax25"; then
    echo "[!] AX.25 module loaded. Vulnerable to CVE-2022-1205 if kernel is unpatched."
fi

if lsmod | grep -q "clk-imx"; then
    echo "[!] i.MX clock module loaded. Vulnerable to CVE-2022-3114 if kernel is unpatched."
fi

# Update package lists and upgrade kernel
echo "[*] Updating package lists..."
sudo apt-get update

echo "[*] Upgrading kernel and related packages..."
sudo apt-get install --only-upgrade linux-image-tegra linux-headers-tegra

# Verify update
echo "[*] Verifying kernel version after update..."
NEW_KERNEL=$(uname -r)
echo "[*] Updated Kernel: $NEW_KERNEL"

if [ "$KERNEL_VERSION" != "$NEW_KERNEL" ]; then
    echo "[+] Kernel updated successfully. Please reboot the system to apply changes."
else
    echo "[!] Kernel version unchanged. Check for held packages or repository issues."
fi

- **Restrict Local Access**: Limit shell access to trusted administrators only. Use `sudo` policies to restrict kernel module loading capabilities.

### 3. Monitoring and Alerting

- **Kernel Crash Monitoring**: Deploy the detection rules provided above to alert on kernel panics or NULL pointer dereference errors.
- **Module Load Auditing**: Monitor for unexpected kernel module loads, particularly those related to AX.25 or clock drivers.

### 4. Vendor Advisory and References

- **Official Advisory**: [USN-8963-1: Linux kernel (NVIDIA Tegra) vulnerabilities](https://ubuntu.com/security/notices/USN-8963-1)
- **CVE-2022-1205**: Race condition in AX.25 protocol
- **CVE-2022-3114**: Null pointer dereference in i.MX clock driver

## Related Resources

[Security Arsenal Managed SOC Services](https://securityarsenal.com/services/managed-soc)
[AlertMonitor Platform](https://securityarsenal.com/products/alertmonitor)
[Book a SOC Assessment](https://securityarsenal.com/contact)
[soc-mdr Intel Hub](https://securityarsenal.com/intel/managed-soc)