Query: write Sigma for Detects an executable initiating a network connection to "ngrok" tunneling domains. Attackers were seen using this "ngro
Matching passage: Sigma rule: Detects an executable initiating a network connection to "ngrok" tunneling domains. Attackers were seen using this "ngro. Logsource: windows / network_connection. Rule: title: Communication To Ngrok Tunneling Service Initiated id: 1d08ac94-400d-4469-a82f-daee9a908849 related: - id: 18249279-932f-45e2-b37a-8925f2597670 type: similar status: test description: 'Detects an executable initiating a network connection to "ngrok" tunneling domains. Attackers were seen using this "ngrok" in order to store their second stage payloads and malware. While communication with such domains can be legitimate, often times is a sign of either data exfiltration by malicious actors or additional download. ' references: - https://twitter.com/hakluke/status/1587733971814977537/photo/1 - https://ngrok.com/docs/secure-tunnels/tunnels/ssh-reverse-tunnel-agent author: Florian Roth (Nextron Systems) date: 2022-11-03 modified: 2024-02-02 tags: - attack.exfiltration - attack.command-and-control - attack.t1567 - attack.t1568.002 - attack.t1572 - attack.t1090 - attack.t1102 - attack.s0508 logsource: category: network_connection product: windows detection: selection: DestinationHostname|contains: - tunnel.us.ngrok.com - tunnel.eu.ngrok.com - tunnel.ap.ngrok.com - tunnel.au.ngrok.com - tunnel.sa.ngrok.com - tunnel.jp.ngrok.com - tunnel.in.ngrok.com condition: selection falsepositives: - Legitimate use of the ngrok service. level: high
Near-miss passage: Sigma rule: Detects the usage of utilities such as 'systemctl', 'service'...etc to stop or disable tools and services on Linux syste. Logsource: linux / process_creation. Rule: title: Disable Or Stop Services id: de25eeb8-3655-4643-ac3a-b662d3f26b6b status: test description: 'Detects the usage of utilities such as ''systemctl'', ''service''...etc to stop or disable tools and services on Linux systems. Attackers may stop or disable security tools and services to evade detection, maintain persistence, or disrupt system operations. ' references: - https://www.trendmicro.com/pl_pl/research/20/i/the-evolution-of-malicious-shell-scripts.html author: Nasreddine Bencherchali (Nextron Systems) date: 2022-09-15 modified: 2025-03-18 tags: - attack.defense-impairment - attack.t1685 - attack.impact - attack.t1489 logsource: category: process_creation product: linux detection: selection: Image|endswith: - /service - /systemctl - /chkconfig CommandLine|contains: - ' stop ' - ' disable ' filter_main_legit_snapd: Image|endswith: /systemctl CommandLine|contains: - --no-reload disable snap-snapd- - ' stop snap-snapd-' filter_main_ssh_preinstall: Image|endswith: /systemctl ParentCommandLine|contains: tmp.ci/preinst upgrade CommandLine|contains|all: - ' stop ' - ssh. filter_main_ubuntu_upgrade: ParentCommandLine|contains: /dpkg/info/ubuntu-pro-client.prerm upgrade Image|endswith: /systemctl filter_optional_aws_agent: Image|endswith: /systemctl CommandLine|endswith: snap.amazon-ssm-agent.amazon-ssm-agent.service condition: selection and not 1 of filter_main_* and not 1 of filter_optional_* falsepositives: - Legitimate administration activities - Some false positives are to be expected. Apply additional filters as needed before pushing to production. level: medium