Detection rules › Elastic

Potential Linux Reverse Shell via Java Shell Execution

Time window
5s
Sequence by
process.entity_id
Source
github.com/elastic/protections-artifacts

Identifies the execution of a Linux shell process from a Java parent application before an incoming network connection. This behavior may indicate reverse shell activity via a Java application.

MITRE ATT&CK coverage

Rule body

[rule]
description = """
Identifies the execution of a Linux shell process from a Java parent application before an incoming network connection.
This behavior may indicate reverse shell activity via a Java application.
"""
id = "41424b6d-8875-409f-a3ab-96792e7c8cd6"
license = "Elastic License v2"
name = "Potential Linux Reverse Shell via Java Shell Execution"
os_list = ["linux"]
version = "1.0.1"

query = '''
sequence by process.entity_id with maxspan=5s
  [process where event.type == "start" and event.action == "exec" and
   process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and
   process.parent.name == "java"
  ]
  [network where event.type == "start" and event.action == "connection_attempted" and
   process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and 
   not (destination.ip == null or destination.ip == "0.0.0.0" or cidrmatch(
     destination.ip, "10.0.0.0/8", "127.0.0.0/8", "169.254.0.0/16", "172.16.0.0/12", "192.0.0.0/24", "192.0.0.0/29",
     "192.0.0.8/32", "192.0.0.9/32", "192.0.0.10/32", "192.0.0.170/32", "192.0.0.171/32", "192.0.2.0/24",
     "192.31.196.0/24", "192.52.193.0/24", "192.168.0.0/16", "192.88.99.0/24", "224.0.0.0/4", "100.64.0.0/10",
     "192.175.48.0/24","198.18.0.0/15", "198.51.100.0/24", "203.0.113.0/24", "240.0.0.0/4", "::1", "FE80::/10",
     "FF00::/8"
     )
   )]
'''

min_endpoint_version = "7.15.0"
optional_actions = []
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0

[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 1

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

[[actions]]
action = "kill_process"
field = "process.parent.entity_id"
state = 1

[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1059"
name = "Command and Scripting Interpreter"
reference = "https://attack.mitre.org/techniques/T1059/"


[threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"
[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1071"
name = "Application Layer Protocol"
reference = "https://attack.mitre.org/techniques/T1071/"


[threat.tactic]
id = "TA0011"
name = "Command and Control"
reference = "https://attack.mitre.org/tactics/TA0011/"

[internal]
min_endpoint_version = "7.15.0"

Stages and Predicates

Ordered sequence: each step below must occur in order within 5s, correlated by process.entity_id.

Stage 1: process

[process where event.type == "start" and event.action == "exec" and
   process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and
   process.parent.name == "java"
  ]

Stage 2: network

[network where event.type == "start" and event.action == "connection_attempted" and
   process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and 
   not (destination.ip == null or destination.ip == "0.0.0.0" or cidrmatch(
     destination.ip, "10.0.0.0/8", "127.0.0.0/8", "169.254.0.0/16", "172.16.0.0/12", "192.0.0.0/24", "192.0.0.0/29",
     "192.0.0.8/32", "192.0.0.9/32", "192.0.0.10/32", "192.0.0.170/32", "192.0.0.171/32", "192.0.2.0/24",
     "192.31.196.0/24", "192.52.193.0/24", "192.168.0.0/16", "192.88.99.0/24", "224.0.0.0/4", "100.64.0.0/10",
     "192.175.48.0/24","198.18.0.0/15", "198.51.100.0/24", "203.0.113.0/24", "240.0.0.0/4", "::1", "FE80::/10",
     "FF00::/8"
     )
   )]

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
destination.ipcidr_match10.0.0.0/8, 127.0.0.0/8, 169.254.0.0/16, 172.16.0.0/12, 192.0.0.0/24, 192.0.0.0/29, 192.0.0.8/32, 192.0.0.9/32, 192.0.0.10/32, 192.0.0.170/32, 192.0.0.171/32, 192.0.2.0/24, 192.31.196.0/24, 192.52.193.0/24, 192.168.0.0/16, 192.88.99.0/24, 224.0.0.0/4, 100.64.0.0/10, 192.175.48.0/24, 198.18.0.0/15, 198.51.100.0/24, 203.0.113.0/24, 240.0.0.0/4, ::1, FE80::/10, FF00::/8excludes:destination.ip
destination.ipeq0.0.0.0excludes:destination.ip field:"destination.ip" value:"0.0.0.0"
destination.ipis_null(no value, null check)excludes:destination.ip

Indicators

These rows show field, operator, and value matches.