Why it exists
Most malware needs to execute code on a device. If only approved software can run, many attacks fail even when they are brand new and unknown to antivirus.
How it works
- 1Inventory the software already in use (often in an audit or learning mode)
- 2Create rules by hash, publisher certificate, path, or parent process
- 3Switch to enforcement: unapproved execution is blocked
- 4Handle exceptions through an approval workflow
Real-world example
An accounting firm allowlists its known apps. An employee opens an email attachment that tries to launch an unknown executable — it is blocked because it isn't on the list.
Common misconceptions
- “Allowlisting is unmanageable.” Modern tools use learning modes and trusted-publisher rules to reduce effort.
- “It replaces EDR.” It prevents execution; it does not investigate incidents.
Benefits
- Strong prevention of unknown executables
- Clear evidence of what software is permitted
Limitations
- Requires an exception process
- Scripts and built-in tools need specific handling
How it differs from related technologies
Antivirus blocks known-bad; allowlisting allows known-good. Privilege management controls admin rights; application control controls execution.
Questions a buyer should ask
- How are software updates trusted automatically?
- How are PowerShell and macros handled?
- What does the exception workflow look like?
Learning path
beginner
- • Read What Is Application Allowlisting?
- • Learn the four rule types
intermediate
- • Read NIST SP 800-167
- • Review the Application Control comparison
advanced
- • Plan a pilot in audit mode
- • Design an exception approval SLA
Check your understanding
In default-deny allowlisting, what happens to an unknown program?