From 8e1dad0aebe7e1f13d61713f7fbdc00ebfde1719 Mon Sep 17 00:00:00 2001
From: Isai <59296946+imays11@users.noreply.github.com>
Date: Thu, 4 Jan 2024 22:14:39 -0500
Subject: [PATCH] [New Rule] Potential Container Escape via Modified
 notify_on_release File (#3244)

* [New Rule] Potential Container Escape via Modified notify_on_release File

This rule detects modification of the cgroup notify_on_release file from inside a container. When the notify_on_release
flag is enabled (1) in a cgroup, then whenever the last task in the cgroup exits or attaches to another cgroup, the
command specified in the release_agent file is run and invoked from the host. A privileged container with SYS_ADMIN
capabilities, enables a threat actor to mount a cgroup directory and modify the notify_on_release flag in order to take
advantage of this feature, which could be used for further privilege escalation and container escapes to the host
machine.

* Apply suggestions from code review

* suggestions from code review

Co-authored-by: Ruben Groenewoud <78494512+Aegrah@users.noreply.github.com>

---------

Co-authored-by: Colson Wilhoit <48036388+DefSecSentinel@users.noreply.github.com>
Co-authored-by: Ruben Groenewoud <78494512+Aegrah@users.noreply.github.com>
---
 ...e_via_modified_notify_on_release_file.toml | 60 +++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 rules/integrations/cloud_defend/privilege_escalation_potential_container_escape_via_modified_notify_on_release_file.toml

diff --git a/rules/integrations/cloud_defend/privilege_escalation_potential_container_escape_via_modified_notify_on_release_file.toml b/rules/integrations/cloud_defend/privilege_escalation_potential_container_escape_via_modified_notify_on_release_file.toml
new file mode 100644
index 000000000..7d3c3b6c2
--- /dev/null
+++ b/rules/integrations/cloud_defend/privilege_escalation_potential_container_escape_via_modified_notify_on_release_file.toml
@@ -0,0 +1,60 @@
+[metadata]
+creation_date = "2023/10/26"
+integration = ["cloud_defend"]
+maturity = "production"
+min_stack_comments = "New Integration: Cloud Defend"
+min_stack_version = "8.8.0"
+updated_date = "2023/12/18"
+
+[rule]
+author = ["Elastic"]
+description = """
+This rule detects modification of the cgroup notify_on_release file from inside a container. When the notify_on_release
+flag is enabled (1) in a cgroup, then whenever the last task in the cgroup exits or attaches to another cgroup, the
+command specified in the release_agent file is run and invoked from the host. A privileged container with SYS_ADMIN
+capabilities, enables a threat actor to mount a cgroup directory and modify the notify_on_release flag in order to take
+advantage of this feature, which could be used for further privilege escalation and container escapes to the host
+machine.
+"""
+from = "now-6m"
+index = ["logs-cloud_defend*"]
+interval = "5m"
+language = "eql"
+license = "Elastic License v2"
+name = "Potential Container Escape via Modified notify_on_release File"
+references = [
+    "https://blog.trailofbits.com/2019/07/19/understanding-docker-container-escapes/",
+    "https://sysdig.com/blog/detecting-mitigating-cve-2022-0492-sysdig/",
+]
+risk_score = 73
+rule_id = "ef65e82c-d8b4-4895-9824-5f6bc6166804"
+severity = "high"
+tags = [
+    "Data Source: Elastic Defend for Containers",
+    "Domain: Container",
+    "OS: Linux",
+    "Use Case: Threat Detection",
+    "Tactic: Privilege Escalation",
+]
+timestamp_override = "event.ingested"
+type = "eql"
+
+query = '''
+file where event.module == "cloud_defend" and event.action == "open" and 
+event.type == "change" and file.name : "notify_on_release"
+'''
+
+
+[[rule.threat]]
+framework = "MITRE ATT&CK"
+[[rule.threat.technique]]
+id = "T1611"
+name = "Escape to Host"
+reference = "https://attack.mitre.org/techniques/T1611/"
+
+
+[rule.threat.tactic]
+id = "TA0004"
+name = "Privilege Escalation"
+reference = "https://attack.mitre.org/tactics/TA0004/"
+