Kythos AI development note · application control
Application allowlisting without turning the endpoint into a dead end.
Kythos AI is developing an application-control workflow focused on trustworthy inventory, signer and path context, staged policy, explainable decisions, exception ownership, and recovery. It is in development—not presented as a released product or a certified control.
The engineering problem
“Allow these hashes” is not an operating model.
Software changes
Browsers, collaboration tools, drivers, installers, scripts, packages, plugins, and internally built software update constantly. A useful policy must recognize controlled change without allowing arbitrary code.
Trust is contextual
A valid signature does not make every binary safe. A writable path does not make every file malicious. Decisions need publisher, chain, reputation, source, path, owner, privilege, and expected behavior.
Recovery must precede enforcement
Application control can block logon, management, updates, recovery tools, drivers, or business workflows. Break-glass, rollback, offline repair, and policy-expiration paths belong in the first design.
Current development direction
A policy lifecycle built around evidence.
Observe
Collect executable, script, installer, packaged-app, driver, signer, hash, path, parent, user, device, and prevalence evidence without making a block decision.
Classify
Separate platform files, managed applications, internal releases, user tools, temporary installers, unknown software, and explicit denials. Preserve the reason for every category.
Simulate
Generate candidate WDAC or AppLocker policy and replay observed activity. Show what would be allowed, denied, or unresolved and which rule made the decision.
Stage
Move from observe to audit, scoped pilot, warning where supported, and enforcement only after application-owner acceptance and recovery validation.
Design principles
What the workflow is being designed to preserve.
Explainability
Every policy decision should identify the rule, source evidence, signer or hash, scope, owner, approval, creation time, review time, and expiration where temporary.
Policy separation
Platform baseline, enterprise publishers, managed paths, internal release signers, exceptions, and explicit denials should be independently reviewable and versioned.
Safe exceptions
Exceptions require an asset and application owner, precise scope, reason, compensating controls, end date, and validation that the exception does not become a broad bypass.
Release integrity
Internal software should be built reproducibly where possible, scanned, signed through a protected process, promoted by environment, and tied to source and release evidence.
Telemetry and health
Blocked and allowed events, policy version, enforcement state, errors, stale clients, unenrolled endpoints, and recovery actions must remain visible to operators.
Fail deliberately
The design must define behavior when identity, reputation, cloud lookup, policy distribution, signing, or management services are unavailable.
Windows implementation path
Use the native control that fits the edition and risk.
Windows Defender Application Control
WDAC is the stronger platform-control direction for modern Windows, including signed policy, audit and enforcement, supplemental policy, managed installer scenarios, and kernel-mode coverage. It demands careful compatibility and recovery engineering.
AppLocker
AppLocker can provide useful publisher, path, hash, packaged-app, script, and installer rules with audit telemetry, especially where edition and management constraints fit. Writable-path rules require particular caution.
ASR and EDR
ASR reduces common abuse paths and EDR supplies behavioral evidence and response. Neither is a substitute for application control, and application control is not a substitute for detection or patching.
Development status
What is and is not being claimed.
- In scope: inventory normalization, signer and release evidence, candidate-policy generation, audit analysis, exception workflow, staged deployment, drift detection, health, and rollback design.
- Not claimed: a generally available product, universal compatibility, zero bypasses, automated CMMC compliance, Microsoft certification, or endorsement by NIST, CISA, MITRE, or another provider.
- Publication standard: future capability and performance claims will be tied to documented versions, test conditions, datasets, failure cases, and measured results.
Windows configuration-management baseline and audit-first script →