Detectionmediumexperimental

Potential Abuse of Linux Magic System Request Key

Detects the potential abuse of the Linux Magic SysRq (System Request) key by adversaries with root or sufficient privileges to silently manipulate or destabilize a system. By writing to /proc/sysrq-trigger, they can crash the system, kill processes, or disrupt forensic analysis—all while bypassing standard logging. Though intended for recovery and debugging, SysRq can be misused as a stealthy post-exploitation tool. It is controlled via /proc/sys/kernel/sysrq or permanently through /etc/sysctl.conf.

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Launch
Milad CheraghiCreated Fri May 23ea61bb82-a5e0-42e6-8537-91d29500f1b9linux
Log Source
Linuxauditd
ProductLinux← raw: linux
Serviceauditd← raw: auditd

Definition

Required auditd configuration: -w /proc/sysrq-trigger -p wa -k sysrq -w /proc/sys/kernel/sysrq -p wa -k sysrq

Detection Logic
Detection Logic1 selector
detection:
    selection:
        type: 'PATH'
        name|endswith:
            # Enable
            - '/sysrq'
            - '/sysctl.conf'
            # Execute
            - '/sysrq-trigger'
    condition: selection
False Positives

Legitimate administrative activity

Rule Metadata
Rule ID
ea61bb82-a5e0-42e6-8537-91d29500f1b9
Status
experimental
Level
medium
Type
Detection
Created
Fri May 23
Path
rules/linux/auditd/path/lnx_auditd_magic_system_request_key.yml
Raw Tags
attack.executionattack.t1059.004attack.impactattack.t1529attack.t1489attack.t1499
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