T1564.011
About this technique
Adversaries may evade defensive mechanisms by executing commands that hide from process interrupt signals. Many operating systems use signals to deliver messages to control process behavior.
Read the full ATT&CK description
Command interpreters often include specific commands/flags that ignore errors and other hangups, such as when the user of the active session logs off.(Citation: Linux Signal Man) These interrupt signals may also be used by defensive tools and/or analysts to pause or terminate specified running processes.
Adversaries may invoke processes using `nohup`, PowerShell `-ErrorAction SilentlyContinue`, or similar commands that may be immune to hangups.(Citation: nohup Linux Man)(Citation: Microsoft PowerShell SilentlyContinue) This may enable malicious commands and malware to continue execution through system events that would otherwise terminate its execution, such as users logging off or the termination of its C2 network connection.
Hiding from process interrupt signals may allow malware to continue execution, but unlike Trap this does not establish Persistence since the process will not be re-invoked once actually terminated.
Curated incident relationships
These associations come from maintained incident records. The recorded confidence is shown when the source record provides it.
Daily items linked through predicted CVEs
A Daily item appears here when it mentions a CVE whose triage artifact predicts this technique. This is not a verified ATT&CK mapping.
Predicted CVE associations
These backfilled or model-produced candidates come from the current triage artifact. They are informational, not official MITRE mappings.