diff --git a/rules/linux/command_and_control_dns_query_to_sus_top_level_domain.toml b/rules/linux/command_and_control_dns_query_to_sus_top_level_domain.toml new file mode 100644 index 00000000000..bbfa69e96b5 --- /dev/null +++ b/rules/linux/command_and_control_dns_query_to_sus_top_level_domain.toml @@ -0,0 +1,125 @@ +[metadata] +creation_date = "2026/07/02" +integration = ["endpoint"] +maturity = "production" +min_stack_version = "9.3.0" +min_stack_comments = "DNS for Linux support was introduced in 9.3.0" +updated_date = "2026/07/02" + +[rule] +author = ["Elastic"] +description = """ +This rule detects DNS queries to commonly abused top level domains. Malware authors may use these +domains to host command and control infrastructure, exfiltrate data, or to download payloads +for later execution. +""" +from = "now-9m" +index = ["logs-endpoint.events.network-*"] +language = "eql" +license = "Elastic License v2" +name = "DNS Request to Suspicious Top Level Domain" +risk_score = 21 +rule_id = "44a2de72-fe41-4558-b7ec-3e42de5f0432" +severity = "low" +tags = [ + "Domain: Endpoint", + "Domain: Network", + "OS: Linux", + "Use Case: Threat Detection", + "Tactic: Command and Control", + "Tactic: Exfiltration", + "Data Source: Elastic Defend", +] +timestamp_override = "event.ingested" +type = "eql" +query = ''' +network where host.os.type == "linux" and dns.question.name != null and process.name != null and +dns.question.name like~ ( + "*.forum", "*.pro", "*.team", "*.lol", "*.kr", "*.ke", "*.nu", "*.space", "*.capital", "*.in", "*.cfd", "*.online", + "*.ru", "*.info", "*.top", "*.buzz", "*.xyz", "*.rest", "*.ml", "*.cf", "*.gq", "*.ga", "*.onion", "*.network", + "*.monster", "*.marketing", "*.cyou", "*.quest", "*.cc", "*.bar", "*.click", "*.cam", "*.surf", "*.tk", "*.shop", + "*.club", "*.icu", "*.pw", "*.ws", "*.fun", "*.life", "*.boats", "*.store", "*.hair", "*.mom", + "*.beauty", "*.bond", "*.biz", "*.live", "*.zone" +) +''' + +[[rule.threat]] +framework = "MITRE ATT&CK" + +[[rule.threat.technique]] +id = "T1071" +name = "Application Layer Protocol" +reference = "https://attack.mitre.org/techniques/T1071/" + +[[rule.threat.technique.subtechnique]] +id = "T1071.004" +name = "DNS" +reference = "https://attack.mitre.org/techniques/T1071/004/" + +[[rule.threat.technique]] +id = "T1090" +name = "Proxy" +reference = "https://attack.mitre.org/techniques/T1090/" + +[[rule.threat.technique.subtechnique]] +id = "T1090.002" +name = "External Proxy" +reference = "https://attack.mitre.org/techniques/T1090/002/" + +[[rule.threat.technique]] +id = "T1102" +name = "Web Service" +reference = "https://attack.mitre.org/techniques/T1102/" + +[[rule.threat.technique.subtechnique]] +id = "T1102.001" +name = "Dead Drop Resolver" +reference = "https://attack.mitre.org/techniques/T1102/001/" + +[[rule.threat.technique.subtechnique]] +id = "T1102.002" +name = "Bidirectional Communication" +reference = "https://attack.mitre.org/techniques/T1102/002/" + +[[rule.threat.technique]] +id = "T1568" +name = "Dynamic Resolution" +reference = "https://attack.mitre.org/techniques/T1568/" + +[[rule.threat.technique.subtechnique]] +id = "T1568.002" +name = "Domain Generation Algorithms" +reference = "https://attack.mitre.org/techniques/T1568/002/" + +[rule.threat.tactic] +id = "TA0011" +name = "Command and Control" +reference = "https://attack.mitre.org/tactics/TA0011/" + +[[rule.threat]] +framework = "MITRE ATT&CK" + +[[rule.threat.technique]] +id = "T1567" +name = "Exfiltration Over Web Service" +reference = "https://attack.mitre.org/techniques/T1567/" + +[[rule.threat.technique.subtechnique]] +id = "T1567.001" +name = "Exfiltration to Code Repository" +reference = "https://attack.mitre.org/techniques/T1567/001/" + +[[rule.threat.technique.subtechnique]] +id = "T1567.002" +name = "Exfiltration to Cloud Storage" +reference = "https://attack.mitre.org/techniques/T1567/002/" + +[[rule.threat.technique.subtechnique]] +id = "T1567.003" +name = "Exfiltration to Text Storage Sites" +reference = "https://attack.mitre.org/techniques/T1567/003/" + +[rule.threat.tactic] +id = "TA0010" +name = "Exfiltration" +reference = "https://attack.mitre.org/tactics/TA0010/" diff --git a/rules/linux/command_and_control_elastic_endpoint_shell_execution.toml b/rules/linux/command_and_control_elastic_endpoint_shell_execution.toml new file mode 100644 index 00000000000..ef1f08e0cbf --- /dev/null +++ b/rules/linux/command_and_control_elastic_endpoint_shell_execution.toml @@ -0,0 +1,110 @@ +[metadata] +creation_date = "2026/07/02" +integration = ["endpoint", "sentinel_one_cloud_funnel"] +maturity = "production" +updated_date = "2026/07/02" + +[rule] +author = ["Elastic"] +description = """ +This rule detects shell executions via Elastic Endpoint. Elastic Endpoint has a built-in response action +console that can be used to execute shell commands on compromised systems. +""" +from = "now-9m" +index = [ + "logs-endpoint.events.process*", + "logs-sentinel_one_cloud_funnel.*", +] +language = "eql" +license = "Elastic License v2" +name = "Shell Execution via Elastic Endpoint" +risk_score = 21 +rule_id = "ef35b103-7fca-4af4-879d-a7e73c918659" +setup = """## Setup + +This rule requires data coming in from Elastic Defend. + +### Elastic Defend Integration Setup +Elastic Defend is integrated into the Elastic Agent using Fleet. Upon configuration, the integration allows the Elastic Agent to monitor events on your host and send data to the Elastic Security app. + +#### Prerequisite Requirements: +- Fleet is required for Elastic Defend. +- To configure Fleet Server refer to the [documentation](https://www.elastic.co/guide/en/fleet/current/fleet-server.html). + +#### The following steps should be executed in order to add the Elastic Defend integration on a Linux System: +- Go to the Kibana home page and click "Add integrations". +- In the query bar, search for "Elastic Defend" and select the integration to see more details about it. +- Click "Add Elastic Defend". +- Configure the integration name and optionally add a description. +- Select the type of environment you want to protect, either "Traditional Endpoints" or "Cloud Workloads". +- Select a configuration preset. Each preset comes with different default settings for Elastic Agent, you can further customize these later by configuring the Elastic Defend integration policy. [Helper guide](https://www.elastic.co/guide/en/security/current/configure-endpoint-integration-policy.html). +- We suggest selecting "Complete EDR (Endpoint Detection and Response)" as a configuration setting, that provides "All events; all preventions" +- Enter a name for the agent policy in "New agent policy name". If other agent policies already exist, you can click the "Existing hosts" tab and select an existing policy instead. +For more details on Elastic Agent configuration settings, refer to the [helper guide](https://www.elastic.co/guide/en/fleet/8.10/agent-policy.html). +- Click "Save and Continue". +- To complete the integration, select "Add Elastic Agent to your hosts" and continue to the next section to install the Elastic Agent on your hosts. +For more details on Elastic Defend refer to the [helper guide](https://www.elastic.co/guide/en/security/current/install-endpoint.html). +""" +severity = "low" +tags = [ + "Domain: Endpoint", + "OS: Linux", + "Use Case: Threat Detection", + "Tactic: Command and Control", + "Tactic: Defense Evasion", + "Tactic: Execution", + "Data Source: Elastic Defend", + "Data Source: SentinelOne", +] +timestamp_override = "event.ingested" +type = "eql" +query = ''' +process where host.os.type == "linux" and event.type == "start" and event.action in ("exec", "start") and +process.parent.executable == "/opt/Elastic/Endpoint/elastic-endpoint" and +process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and +process.args in ("-c", "-cl", "-lc", "--command") +''' + +[[rule.threat]] +framework = "MITRE ATT&CK" + + [rule.threat.tactic] + name = "Command and Control" + id = "TA0011" + reference = "https://attack.mitre.org/tactics/TA0011/" + + [[rule.threat.technique]] + name = "Remote Access Tools" + id = "T1219" + reference = "https://attack.mitre.org/techniques/T1219/" + +[[rule.threat]] +framework = "MITRE ATT&CK" + + [rule.threat.tactic] + name = "Defense Evasion" + id = "TA0005" + reference = "https://attack.mitre.org/tactics/TA0005/" + + [[rule.threat.technique]] + id = "T1218" + name = "System Binary Proxy Execution" + reference = "https://attack.mitre.org/techniques/T1218/" + +[[rule.threat]] +framework = "MITRE ATT&CK" + + [rule.threat.tactic] + name = "Execution" + id = "TA0002" + reference = "https://attack.mitre.org/tactics/TA0002/" + + [[rule.threat.technique]] + id = "T1059" + name = "Command and Scripting Interpreter" + reference = "https://attack.mitre.org/techniques/T1059/" + + [[rule.threat.technique.subtechnique]] + name = "Unix Shell" + id = "T1059.004" + reference = "https://attack.mitre.org/techniques/T1059/004/" diff --git a/rules/linux/execution_payload_downloaded_by_interpreter_and_piped_to_interpreter.toml b/rules/linux/execution_payload_downloaded_by_interpreter_and_piped_to_interpreter.toml new file mode 100644 index 00000000000..440156eb8a3 --- /dev/null +++ b/rules/linux/execution_payload_downloaded_by_interpreter_and_piped_to_interpreter.toml @@ -0,0 +1,130 @@ +[metadata] +creation_date = "2026/07/02" +integration = ["endpoint"] +maturity = "production" +updated_date = "2026/07/02" + +[rule] +author = ["Elastic"] +description = """ +This rule detects when a payload is downloaded by an interpreter, and piped to an interpreter. Attackers may use this +technique to download and execute payloads for various malicious purposes, such as establishing persistence or +exfiltrating data. +""" +from = "now-9m" +index = ["logs-endpoint.events.network*", "logs-endpoint.events.process*"] +language = "eql" +license = "Elastic License v2" +name = "Payload Downloaded by Interpreter and Piped to Interpreter" +risk_score = 47 +rule_id = "5dc3519c-1f56-42fc-9a70-7e6b705c2781" +setup = """## Setup + +This rule requires data coming in from Elastic Defend. + +### Elastic Defend Integration Setup +Elastic Defend is integrated into the Elastic Agent using Fleet. Upon configuration, the integration allows the Elastic Agent to monitor events on your host and send data to the Elastic Security app. + +#### Prerequisite Requirements: +- Fleet is required for Elastic Defend. +- To configure Fleet Server refer to the [documentation](https://www.elastic.co/guide/en/fleet/current/fleet-server.html). + +#### The following steps should be executed in order to add the Elastic Defend integration on a Linux System: +- Go to the Kibana home page and click "Add integrations". +- In the query bar, search for "Elastic Defend" and select the integration to see more details about it. +- Click "Add Elastic Defend". +- Configure the integration name and optionally add a description. +- Select the type of environment you want to protect, either "Traditional Endpoints" or "Cloud Workloads". +- Select a configuration preset. Each preset comes with different default settings for Elastic Agent, you can further customize these later by configuring the Elastic Defend integration policy. [Helper guide](https://www.elastic.co/guide/en/security/current/configure-endpoint-integration-policy.html). +- We suggest selecting "Complete EDR (Endpoint Detection and Response)" as a configuration setting, that provides "All events; all preventions" +- Enter a name for the agent policy in "New agent policy name". If other agent policies already exist, you can click the "Existing hosts" tab and select an existing policy instead. +For more details on Elastic Agent configuration settings, refer to the [helper guide](https://www.elastic.co/guide/en/fleet/8.10/agent-policy.html). +- Click "Save and Continue". +- To complete the integration, select "Add Elastic Agent to your hosts" and continue to the next section to install the Elastic Agent on your hosts. +For more details on Elastic Defend refer to the [helper guide](https://www.elastic.co/guide/en/security/current/install-endpoint.html). +""" +severity = "medium" +tags = [ + "Domain: Endpoint", + "OS: Linux", + "Use Case: Threat Detection", + "Tactic: Execution", + "Tactic: Command and Control", + "Tactic: Defense Evasion", + "Data Source: Elastic Defend", +] +type = "eql" +query = ''' +sequence by host.id, process.parent.entity_id, process.working_directory with maxspan=1s + [network where host.os.type == "linux" and event.type == "start" and event.action == "connection_attempted" and ( + process.name like ( + "bash", "dash", "sh", "tcsh", "tclsh", "wish", "csh", "zsh", "ksh", "fish", + "mksh", "busybox", "rscript", "r", "julia", "mono", "dotnet", "groovy", "kotlin", + "scala", "erlang", "escript", "ocaml", "ocamlopt", "ld.so", "ld-linux-x86-64.so.2", + "ld-musl-x86_64.so.1", "awk", "gawk", "mawk", "nawk", "node", "nodejs", "deno", + "env", "timeout", "nice", "stdbuf", "setsid", "setarch", "unshare", "nsenter", "flock", + "runuser", "sudo", "snap" + ) or + process.name like ("python*", "perl*", "ruby*", "lua*", "php*", "qemu-*-static") + ) 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" + ) + )] + [process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and ( + process.name like ( + "bash", "dash", "sh", "tcsh", "tclsh", "wish", "csh", "zsh", "ksh", "fish", + "mksh", "busybox", "rscript", "r", "julia", "mono", "dotnet", "groovy", "kotlin", + "scala", "erlang", "escript", "ocaml", "ocamlopt", "ld.so", "ld-linux-x86-64.so.2", + "ld-musl-x86_64.so.1", "awk", "gawk", "mawk", "nawk", "node", "nodejs", "deno" + ) or + process.name like ("python*", "perl*", "ruby*", "lua*", "php*") + ) and ( + stringcontains(process.executable, process.command_line) or + stringcontains(process.name, process.command_line) + ) and + process.args_count == 1] +''' + +[[rule.threat]] +framework = "MITRE ATT&CK" + +[rule.threat.tactic] +name = "Execution" +id = "TA0002" +reference = "https://attack.mitre.org/tactics/TA0002/" + +[[rule.threat.technique]] +id = "T1059" +name = "Command and Scripting Interpreter" +reference = "https://attack.mitre.org/techniques/T1059/" + +[[rule.threat.technique.subtechnique]] +id = "T1059.004" +name = "Unix Shell" +reference = "https://attack.mitre.org/techniques/T1059/004/" + +[[rule.threat]] +framework = "MITRE ATT&CK" + +[rule.threat.tactic] +name = "Command and Control" +id = "TA0011" +reference = "https://attack.mitre.org/tactics/TA0011/" + +[[rule.threat.technique]] +name = "Application Layer Protocol" +id = "T1071" +reference = "https://attack.mitre.org/techniques/T1071/" + +[[rule.threat]] +framework = "MITRE ATT&CK" + +[rule.threat.tactic] +name = "Defense Evasion" +id = "TA0005" +reference = "https://attack.mitre.org/tactics/TA0005/" diff --git a/rules/linux/execution_suspicious_xdg_open_command_execution.toml b/rules/linux/execution_suspicious_xdg_open_command_execution.toml new file mode 100644 index 00000000000..6a09da8d60c --- /dev/null +++ b/rules/linux/execution_suspicious_xdg_open_command_execution.toml @@ -0,0 +1,100 @@ +[metadata] +creation_date = "2026/07/02" +integration = ["endpoint", "crowdstrike", "sentinel_one_cloud_funnel", "auditd_manager"] +maturity = "production" +updated_date = "2026/07/02" + +[rule] +author = ["Elastic"] +description = """ +This rule monitors for the execution of the xdg-open process that is typically used to open documents and +URLs in the user's preferred desktop application. Attackers may use this command to trick users into opening +malicious documents or URLs to gain access to the target system. +""" +from = "now-9m" +index = [ + "endgame-*", + "logs-crowdstrike.fdr*", + "logs-endpoint.events.process*", + "logs-sentinel_one_cloud_funnel.*", + "logs-auditd_manager.auditd-*", +] +language = "eql" +license = "Elastic License v2" +name = "XDG-Open Command Execution" +risk_score = 47 +rule_id = "904023d7-8307-48bc-ad49-c454dfc2fae3" +setup = """## Setup + +This rule requires data coming in from Elastic Defend. + +### Elastic Defend Integration Setup +Elastic Defend is integrated into the Elastic Agent using Fleet. Upon configuration, the integration allows the Elastic Agent to monitor events on your host and send data to the Elastic Security app. + +#### Prerequisite Requirements: +- Fleet is required for Elastic Defend. +- To configure Fleet Server refer to the [documentation](https://www.elastic.co/guide/en/fleet/current/fleet-server.html). + +#### The following steps should be executed in order to add the Elastic Defend integration on a Linux System: +- Go to the Kibana home page and click "Add integrations". +- In the query bar, search for "Elastic Defend" and select the integration to see more details about it. +- Click "Add Elastic Defend". +- Configure the integration name and optionally add a description. +- Select the type of environment you want to protect, either "Traditional Endpoints" or "Cloud Workloads". +- Select a configuration preset. Each preset comes with different default settings for Elastic Agent, you can further customize these later by configuring the Elastic Defend integration policy. [Helper guide](https://www.elastic.co/guide/en/security/current/configure-endpoint-integration-policy.html). +- We suggest selecting "Complete EDR (Endpoint Detection and Response)" as a configuration setting, that provides "All events; all preventions" +- Enter a name for the agent policy in "New agent policy name". If other agent policies already exist, you can click the "Existing hosts" tab and select an existing policy instead. +For more details on Elastic Agent configuration settings, refer to the [helper guide](https://www.elastic.co/guide/en/fleet/8.10/agent-policy.html). +- Click "Save and Continue". +- To complete the integration, select "Add Elastic Agent to your hosts" and continue to the next section to install the Elastic Agent on your hosts. +For more details on Elastic Defend refer to the [helper guide](https://www.elastic.co/guide/en/security/current/install-endpoint.html). +""" +severity = "medium" +tags = [ + "Domain: Endpoint", + "OS: Linux", + "Use Case: Threat Detection", + "Tactic: Execution", + "Data Source: Elastic Endgame", + "Data Source: Elastic Defend", + "Data Source: Crowdstrike", + "Data Source: SentinelOne", + "Data Source: Auditd Manager", +] +timestamp_override = "event.ingested" +type = "eql" +query = ''' +process where host.os.type == "linux" and event.type == "start" and +event.action in ("exec", "exec_event", "executed", "process_started", "ProcessRollup2") and ( + process.name == "xdg-open" or + process.args in ("/bin/xdg-open", "/usr/bin/xdg-open", "/usr/local/bin/xdg-open", "xdg-open") +) +''' + +[[rule.threat]] +framework = "MITRE ATT&CK" + + [rule.threat.tactic] + name = "Execution" + id = "TA0002" + reference = "https://attack.mitre.org/tactics/TA0002/" + + [[rule.threat.technique]] + id = "T1204" + name = "User Execution" + reference = "https://attack.mitre.org/techniques/T1204/" + + [[rule.threat.technique.subtechnique]] + id = "T1204.001" + name = "Malicious Link" + reference = "https://attack.mitre.org/techniques/T1204/001/" + + [[rule.threat.technique.subtechnique]] + id = "T1204.002" + name = "Malicious File" + reference = "https://attack.mitre.org/techniques/T1204/002/" + + [[rule.threat.technique.subtechnique]] + id = "T1204.004" + name = "Malicious Copy and Paste" + reference = "https://attack.mitre.org/techniques/T1204/004/"