Detectionlowexperimental

Linux Setgid Capability Set on a Binary via Setcap Utility

Detects the use of the 'setcap' utility to set the 'setgid' capability (cap_setgid) on a binary file. This capability allows a non privileged process to make arbitrary manipulations of group IDs (GIDs), including setting its current GID to a value that would otherwise be restricted (i.e. GID 0, the root group). This behavior can be used by adversaries to backdoor a binary in order to escalate privileges again in the future if needed.

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Launch

Luc GénauxCreated Sat Jan 243a716279-c18c-4488-83be-f9ececbfb9fclinux

Log Source

LinuxProcess Creation

ProductLinux← raw: linux

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection:
        Image|endswith: '/setcap'
        CommandLine|contains: 'cap_setgid'
    condition: selection

False Positives

Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

References

MITRE ATT&CK

Tactics

TA0004 · Privilege Escalation TA0005 · Defense Evasion TA0003 · Persistence

Techniques

T1548 · Abuse Elevation Control Mechanism T1554 · Compromise Host Software Binary

Rule Metadata

Rule ID

3a716279-c18c-4488-83be-f9ececbfb9fc

Status

experimental

Level

low

Type

Detection

Created

Sat Jan 24

Author

Luc Génaux

Path

rules/linux/process_creation/proc_creation_lnx_cap_setgid.yml

Raw Tags

attack.privilege-escalationattack.defense-evasionattack.persistenceattack.t1548attack.t1554

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