process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and
process.command_line : (
  "*/etc/sysctl.conf*", "*/etc/sysctl.d/*", "*/proc/sys/kernel/nmi_watchdog*",
  "*/proc/sys/vm/nr_hugepages*", "*/proc/sys/kernel/yama/ptrace_scope*",
  "*/proc/sys/kernel/randomize_va_space*", "*/proc/sys/vm/drop_caches*",
  "*/proc/sys/kernel/sysrq*", "*grsecurity*", "*exec-shield*",
  "*kernel.randomize_va_space*", "*kernel.yama.ptrace_scope*",
  "*kernel.nmi_watchdog*", "*vm.nr_hugepages*", "*vm.drop_caches*",
  "*kernel.sysrq*"
) and
process.parent.executable != null and 
(
  (process.name == "tee" and process.args like "-*a*") or // also detects --append
  (process.name == "cat" and not process.parent.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish")) or
  (process.name == "grep" and process.args_count == 3 and not process.parent.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish")) or
  (process.name == "sysctl" and process.args like ("*-w*", "*--write*", "*=*")) or
  (process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and process.args == "-c" and process.args : "*echo *")
)