Potential Privilege Escalation via a SUID/SGID Binary

[rule]
description = """
This rule detects potential privilege escalation under the root effective user when the real user and parent user are
not root, indicative of the execution of binaries with SUID or SGID bits set. Attackers may abuse SUID/SGID binaries to
escalate their privileges to root, using exploits or misconfigurations.
"""
id = "6ac2717b-a63d-4697-b01e-918388bdc762"
license = "Elastic License v2"
name = "Potential Privilege Escalation via a SUID/SGID Binary"
os_list = ["linux"]
version = "1.0.4"

query = '''
process where event.type == "start" and event.action == "exec" and (
  (process.user.id == 0 and process.real_user.id != 0 and process.parent.user.id != 0) or
  (process.group.id == 0 and process.real_group.id != 0 and process.parent.group.id != 0)
) and
(
  stringcontains(process.executable, process.command_line) or
  stringcontains(process.name, process.command_line)
) and
(
  process.parent.name like (".*", "python*", "perl*", "ruby*", "lua*", "php*", "node", "deno", "bun", "java") or
  process.parent.executable like ("./*", "/tmp/*", "/var/tmp/*", "/dev/shm/*", "/run/user/*", "/var/run/user/*", "/home/*/*") or
  (
    process.parent.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish", "mksh") and
    process.parent.args in ("-c", "-cl", "-lc", "--command", "-ic", "-ci", "-bash", "-sh", "-zsh", "-dash", "-fish", "-ksh", "-mksh") and
    process.parent.args_count <= 4
  )
) and
not (
  /* Covered by b1d415dc-796a-48f1-944f-4bb6037b2450 */
  process.name in (
    "unix_chkpwd", "fusermount", "fusermount3", "umount", "newgrp", "chsh", "sudoedit", "gpasswd", "chfn", "polkit-agent-helper-1",
    "dbus-daemon-launch-helper", "ssh-keysign", "pam_extrausers_chkpwd", "expiry", "chage", "wall", "bsd-write", "ssh-agent",
    "ping6", "traceroute", "mtr", "ntfs-3g", "Xorg.wrap", "chrome-sandbox", "bwrap", "hostname", "sudo"
  ) or
  (
    /* Covered by 83b0e48b-f42e-4323-b8cd-386619a96d35 */
    (process.name == "su" and process.args_count <= 2) or
    (process.name == "pkexec" and process.args_count == 1) or
    (process.name == "passwd" and process.args_count <= 2)
  ) or
  (process.name == "mount" and process.args_count <= 2) or
  process.parent.executable like "/u0*/*" or
  process.name like "python*" or
  process.executable like (
    "/opt/psa/admin/bin/*", "/usr/lib/landscape/apt-update", "/usr/sbin/login_duo", "/usr/bin/nvidia-modprobe", "/usr/bin/proxmox-mail-forward",
    "/opt/andrisoft/bin/WANmaintenance", "/ora/SW/em_agent/*", "/opt/OracleHomes/agent_home/*", "/opt/rsa/am/utils/lib/linux-x86_64/*",
    "/usr/libexec/spice-client-glib-usb-acl-helper", "/tmp/newroot/usr/bin/vmware-user-suid-wrapper", "/home/*/sqllib/adm/db2start",
    "/home/*/sqllib/adm/db2stop", "/*/app/oracle/product/*/sbin/nmo", "/opt/data/db2inst1/sqllib/adm/db2stop", "/opt/data/db2inst1/sqllib/adm/db2start",
    "/usr/local/sbin/uid_gid_mapping", "/usr/bin/crontab", "/home/db2inst1/sqllib/adm/db2chparm", "/vz/root/*/opt/psa/admin/bin/osdetect",
    "/data/app/oracle/agent/*", "/usr/lib/plesk-*/msmtp-pwdeval", "/usr/sbin/mount.nfs"
  ) or
  process.command_line in ("/usr/bin/nvidia-modprobe", "/usr/sbin/login_duo")
)
'''

min_endpoint_version = "8.2.0"
optional_actions = []
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0

[[actions]]
action = "kill_process"
field = "process.parent.entity_id"
state = 0

[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1068"
name = "Exploitation for Privilege Escalation"
reference = "https://attack.mitre.org/techniques/T1068/"

[[threat.technique]]
id = "T1548"
name = "Abuse Elevation Control Mechanism"
reference = "https://attack.mitre.org/techniques/T1548/"
[[threat.technique.subtechnique]]
id = "T1548.001"
name = "Setuid and Setgid"
reference = "https://attack.mitre.org/techniques/T1548/001/"

[[threat.technique.subtechnique]]
id = "T1548.003"
name = "Sudo and Sudo Caching"
reference = "https://attack.mitre.org/techniques/T1548/003/"



[threat.tactic]
id = "TA0004"
name = "Privilege Escalation"
reference = "https://attack.mitre.org/tactics/TA0004/"

[internal]
min_endpoint_version = "8.2.0"