Binfmt Configuration File Creation

Last updated 2 days ago on 2026-08-25

Created 2 days ago on 2026-08-25

About

This rule detects the creation of a binfmt configuration file. Binfmt is a utility that is used to configure the behavior of the Linux kernel when executing binary files. By creating a malicious binfmt configuration file, threat actors can execute a backdoor script or command on the target system.

Tags

Domain: EndpointOS: LinuxPlatform: LinuxUse Case: Threat DetectionTactic: PersistenceData Source: Elastic DefendLanguage: eql

Severity

low

Risk Score

MITRE ATT&CK™

Persistence (TA0003)(external, opens in a new tab or window)

↳ Event Triggered Execution (T1546)(external, opens in a new tab or window)

License

Elastic License v2(external, opens in a new tab or window)

Definition

Rule Type: Event Correlation Rule
Integration Pack: Prebuilt Security Detection Rules
Index Patterns: logs-endpoint.events.file*
Related Integrations: endpoint(external, opens in a new tab or window)
Query

✄𐘗text code block:
✄𐘗file where host.os.type == "linux" and event.action != "deletion" and process.executable != null and
file.path like (
  "/etc/binfmt.d/*.conf", "/run/binfmt.d/*.conf", "/usr/local/lib/binfmt.d/*.conf", "/usr/lib/binfmt.d/*.conf",
  "/proc/sys/fs/binfmt_misc/register", "/proc/sys/fs/binfmt_misc/*"
) and
not (
  file.path like (
    "/usr/lib/binfmt.d/python3.*.conf", "/usr/lib/binfmt.d/qemu-*-static.conf",
    "/proc/sys/fs/binfmt_misc/status"
  ) or
  process.executable == "/usr/lib/systemd/systemd-binfmt"
)

Install detection rules in Elastic Security

Detect Binfmt Configuration File Creation in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).