Detection rules › Splunk

Linux Suspicious GCC Invocation Building Init Shared Object

Status
production
Severity
medium
Group by
CurrentDirectory, IntegrityLevel, command_line, computer_name, event_action, original_file_name, parent_command_line, parent_process_guid, parent_process_id, parent_process_name, process_guid, process_hash, process_id, process_name, user, user_id, vendor_product
Author
Raven Tait, Splunk
Source
github.com/splunk/security_content

The following analytic detects compiler usage with flags commonly used to create shared libraries that auto-run initialization functions, which are often associated with local privilege escalation exploits.

Known false positives

  • Legitimate developers may use these GCC flags when building shared libraries that require initialization functions. Filter based on known development environments and trusted users.

MITRE ATT&CK coverage

Telemetry coverage

PlatformRecord / event type
LinuxEvent ID 1: Process Create

Rule body

name: Linux Suspicious GCC Invocation Building Init Shared Object
id: 9dbf4a61-0493-43bd-932c-532ba7671a7a
version: 1
creation_date: '2026-07-08'
modification_date: '2026-07-08'
author: Raven Tait, Splunk
status: production
type: TTP
description: |-
    The following analytic detects compiler usage with flags commonly used to create shared libraries that auto-run initialization functions, which are often associated with local privilege escalation exploits.
data_source:
    - Sysmon for Linux EventID 1
search: |-
    | tstats `security_content_summariesonly`
      count min(_time) as firstTime max(_time) as lastTime
    
    FROM datamodel=Endpoint.Processes WHERE
    
    Processes.process_name IN (
        "*x86_64-linux-gnu-gcc*",
        "cc",
        "g++",
        "gcc-*",
        "gcc"
    )
    Processes.process="*-shared*"
    Processes.process="*-Wl,-init,*"
    Processes.process="*.so*"
    
    BY Processes.action Processes.dest Processes.original_file_name
       Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
       Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
       Processes.process Processes.process_current_directory Processes.process_exec
       Processes.process_guid Processes.process_hash Processes.process_id
       Processes.process_integrity_level Processes.process_name Processes.process_path
       Processes.user Processes.user_id Processes.vendor_product
    
    | `drop_dm_object_name(Processes)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `linux_suspicious_gcc_invocation_building_init_shared_object_filter`
how_to_implement: |-
    The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
known_false_positives: |-
    Legitimate developers may use these GCC flags when building shared libraries that require initialization functions. Filter based on known development environments and trusted users.
references:
    - https://www.bleepingcomputer.com/news/security/cisa-warns-of-critical-linux-sudo-flaw-exploited-in-attacks/
    - https://github.com/pr0v3rbs/CVE-2025-32463_chwoot
finding:
    title: Suspicious GCC Invocation Building Init Shared Object identified on [$dest$] via [$process_name$] with the Command Line [$process$]
    entity:
        field: dest
        type: system
        score: 50
threat_objects:
    - field: process_name
      type: process_name
    - field: process
      type: process
analytic_story:
    - Linux Privilege Escalation
    - Linux Post-Exploitation
    - Linux Persistence Techniques
asset_type: Endpoint
cve:
    - CVE-2025-32463
mitre_attack_id:
    - T1129
    - T1068
    - T1608
    - T1027.004
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint

Stages and Predicates

Stage 1: tstats

| tstats `security_content_summariesonly`
  count min(_time) as firstTime max(_time) as lastTime

FROM datamodel=Endpoint.Processes WHERE

Processes.process_name IN (
    "*x86_64-linux-gnu-gcc*",
    "cc",
    "g++",
    "gcc-*",
    "gcc"
)
Processes.process="*-shared*"
Processes.process="*-Wl,-init,*"
Processes.process="*.so*"

BY Processes.action Processes.dest Processes.original_file_name
   Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
   Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
   Processes.process Processes.process_current_directory Processes.process_exec
   Processes.process_guid Processes.process_hash Processes.process_id
   Processes.process_integrity_level Processes.process_name Processes.process_path
   Processes.user Processes.user_id Processes.vendor_product

Stage 2: search

| `drop_dm_object_name(Processes)`

Stage 3: search

| `security_content_ctime(firstTime)`

Stage 4: search

| `security_content_ctime(lastTime)`

Stage 5: search

| `linux_suspicious_gcc_invocation_building_init_shared_object_filter`

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Processes.processeq
  • "*-Wl,-init,*"
  • "*-shared*"
  • "*.so*"
field:"CommandLine" kind:eq
Processes.process_namein
  • "*x86_64-linux-gnu-gcc*"
  • "cc"
  • "g++"
  • "gcc"
  • "gcc-*"
field:"process_name" kind:in