New Rule to identify defense evasion via PRoot (#2625)

rules/linux/defense_evasion_potential_proot_exploits.toml

@@ -0,0 +1,54 @@
+[metadata]
+creation_date = "2023/03/07"
+integration = ["endpoint"]
+maturity = "production"
+min_stack_comments = "New fields added: required_fields, related_integrations, setup"
+min_stack_version = "8.3.0"
+updated_date = "2023/03/07"
+
+[rule]
+author = ["Elastic"]
+description = """
+Identifies the execution of the PRoot utility, an open-source tool for user-space implementation of
+chroot, mount --bind, and binfmt_misc. Adversaries can leverage an open-source tool PRoot
+to expand the scope of their operations to multiple Linux distributions and simplify their necessary efforts.
+In a normal threat scenario, the scope of an attack is limited by the varying configurations of each Linux distribution.
+With PRoot, it provides an attacker with a consistent operational environment across different Linux distributions,
+such as Ubuntu, Fedora, and Alpine. PRoot also provides emulation capabilities that allow for malware built on other
+architectures, such as ARM, to be run.The post-exploitation technique called bring your own filesystem (BYOF),
+can be used by the threat actors to execute malicious payload or elevate privileges or perform network scans or
+orchestrate another attack on the environment. Although PRoot was originally not developed with malicious intent
+it can be easily tuned to work for one.
+"""
+from = "now-9m"
+index = ["logs-endpoint.events.*"]
+language = "eql"
+license = "Elastic License v2"
+name = "Potential Defense Evasion via PRoot"
+references = [
+    "https://proot-me.github.io/",
+]
+risk_score = 47
+rule_id = "5c9ec990-37fa-4d5c-abfc-8d432f3dedd0"
+severity = "medium"
+tags = ["Elastic", "Host", "Linux", "Threat Detection", "Defense Evasion"]
+timestamp_override = "event.ingested"
+type = "eql"
+query = '''
+process where  event.action == "exec" and process.parent.name =="proot" and host.os.type == "linux"
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1211"
+name = "Exploitation for Defense Evasion"
+reference = "https://attack.mitre.org/techniques/T1211/"
+
+
+[rule.threat.tactic]
+id = "TA0005"
+name = "Defense Evasion"
+reference = "https://attack.mitre.org/tactics/TA0005/"
+