---
title: Suspicious Kernel Module Loading Activity
id: 87a3f2b1-9c4d-4e6a-a5b8-2d9e3f4a5c6d
status: experimental
description: Detects suspicious kernel module loading patterns potentially related to kernel exploitation
author: Security Arsenal
date: 2026/04/14
tags:
  - attack.privilege_escalation
  - attack.t1068
logsource:
  category: process_creation
  product: linux
detection:
  selection:
    Image|endswith: '/insmod'
    CommandLine|contains:
      - 'force'
      - ' tainted'
  condition: selection
falsepositives:
  - Legitimate driver installation
  - System administration activities
level: high
---
title: Unexpected SUID Binary Creation
id: 9b4c3d2e-0a5f-4b6c-8d9e-1f2a3b4c5d6e
status: experimental
description: Detects creation of SUID binaries in common locations that may indicate privilege escalation
author: Security Arsenal
date: 2026/04/14
tags:
  - attack.privilege_escalation
  - attack.t1068
logsource:
  category: file_event
  product: linux
detection:
  selection:
    TargetFilename|contains:
      - '/bin/'
      - '/usr/bin/'
      - '/sbin/'
      - '/usr/sbin/'
  filter_main:
    TargetFilename|contains:
      - '.rpmnew'
      - '.dpkg-'
  condition: selection and not filter_main
falsepositives:
  - Legitimate software updates
  - Package management operations
level: medium
---
title: Abnormal System Call Patterns
id: 7c6d5e4f-1a9b-4c7d-9e2f-3b4a5c6d7e8f
status: experimental
description: Detects unusual system call patterns potentially indicative of kernel-level exploitation
author: Security Arsenal
date: 2026/04/14
tags:
  - attack.defense_evasion
  - attack.t1211
logsource:
  category: process_creation
  product: linux
detection:
  selection:
    Image|endswith:
      - '/strace'
      - '/ptrace'
    CommandLine|contains:
      - 'mmap'
      - 'mprotect'
  condition: selection
falsepositives:
  - Debugging activities
  - Developer operations
level: high

// Hunt for unusual kernel module loading activity
Syslog
| where ProcessName contains "insmod" or ProcessName contains "modprobe"
| where SyslogMessage contains "force" or SyslogMessage contains "tainted"
| project TimeGenerated, HostName, ProcessName, SyslogMessage, ProcessID
| sort by TimeGenerated desc

// Detect potential privilege escalation via suspicious SUID changes
Syslog
| where SyslogMessage contains "chmod" and SyslogMessage contains "+s"
| where SyslogMessage contains "/bin/" or SyslogMessage contains "/usr/bin/" or SyslogMessage contains "/sbin/"
| project TimeGenerated, HostName, SyslogMessage, SourceProcess, ProcessID
| sort by TimeGenerated desc

// Look for process memory protection changes (mprotect) with executable permissions
DeviceProcessEvents
| where ProcessCommandLine contains "mprotect" and (ProcessCommandLine contains "PROT_EXEC" or ProcessCommandLine contains "7")
| project Timestamp, DeviceName, InitiatingProcessAccountName, ProcessCommandLine, InitiatingProcessFileName
| sort by Timestamp desc

-- Check for recently modified kernel modules
SELECT FullPath, Mtime, Size, Mode.String
FROM glob(globs='/lib/modules/*/kernel/**/*.ko')
WHERE Mtime > now() - 24h

-- Hunt for SUID binaries in system paths
SELECT FullPath, Mode.String, Mtime, Size
FROM glob(globs=['/bin/*', '/usr/bin/*', '/sbin/*', '/usr/sbin/*'])
WHERE Mode.String =~ 's' AND Mtime > now() - 7d

-- Investigate processes with unusual memory region permissions
SELECT Pid, Name, CommandLine, Username, CreateTime
FROM pslist()
WHERE Name IN ('strace', 'ptrace', 'gdb') AND CreateTime > now() - 24h

#!/bin/bash
# Linux Kernel FIPS Vulnerability Remediation Script for USN-8492-5
# This script checks for the vulnerability and applies the necessary updates

set -e

echo "Starting Linux Kernel FIPS Vulnerability Remediation (USN-8492-5)"
echo "Current date: $(date)"
echo "Checking system information..."

# Check if system is Ubuntu
if [ ! -f /etc/lsb-release ]; then
    echo "ERROR: This script is designed for Ubuntu systems."
    exit 1
fi

source /etc/lsb-release

echo "Detected Ubuntu version: $DISTRIB_RELEASE"

# Check current kernel version
echo "Current kernel version: $(uname -r)"

# Update package list
echo "Updating package lists..."
apt-get update -q

# Check if security update is available
if apt-cache policy linux-image-fips | grep -q "USN-8492-5"; then
    echo "Security update USN-8492-5 is available and will be installed."
    
    # Install the security update
    echo "Installing security update..."
    apt-get install -y linux-image-fips linux-headers-fips
    
    echo "Update installed successfully."
    
    # Ask user if they want to reboot now
    echo "A system reboot is required to apply the kernel update."
    read -p "Reboot now? (y/n) " -n 1 -r
    echo
    if [[ $REPLY =~ ^[Yy]$ ]]; then
        echo "Rebooting system..."
        reboot
    else
        echo "Please remember to reboot the system to apply the kernel update."
    fi
else
    echo "No USN-8492-5 update found or system may already be patched."
fi

# Check for vulnerable kernel modules still loaded
echo "Checking for potentially vulnerable kernel modules..."
modinfo rnbd_server > /dev/null 2>&1 && echo "WARNING: RNBD server module loaded (may be vulnerable)" || true
modinfo rnbd_client > /dev/null 2>&1 && echo "WARNING: RNBD client module loaded (may be vulnerable)" || true
modinfo ublk_drv > /dev/null 2>&1 && echo "WARNING: Ublk driver module loaded (may be vulnerable)" || true

echo "Remediation script completed."