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Security Policies extend the Myrmex RBAC system with Attribute-Based Access Control (ABAC), allowing you to enforce environmental conditions on user access. While RBAC controls who can do what, security policies add when, where, and how.

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How Security Policies Work

Every policy has four key elements:

Effect

Deny or Allow. Determines what happens when conditions are (or aren’t) met.

Conditions

Environmental attributes to evaluate: source IP, time, day of week, MFA status, device type, or user agent.

Targeting

Which permissions, roles, devices, or integrations this policy applies to. Empty targeting means “applies to all.”

Priority

Numeric value that determines evaluation order. Higher priority policies are evaluated first.

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Deny vs. Allow Policies

Understanding the two policy effects is critical:
“Block access if conditions are NOT met.”The most common type. A Deny policy defines requirements that must be satisfied — if the user’s request does not meet the conditions, access is blocked.Example: Business Hours Only
  • Effect: deny
  • Condition: time_of_day between 08:00 and 18:00
  • Meaning: “Deny access if the request is NOT between 08:00–18:00”
  • Result: Access outside business hours is blocked
Example: Corporate VPN Required
  • Effect: deny
  • Condition: source_ip in 203.0.113.0/24
  • Meaning: “Deny access if the request is NOT from the corporate VPN public IP range”
  • Result: Access from outside the corporate VPN is blocked
Deny policies are evaluated before Allow policies (when they have the same priority). Always test policies in a non-production context before applying to critical roles.

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Targeting: Controlling Policy Scope

Policies can target specific permissions, roles, devices, or integrations. When a targeting field is left empty, the policy applies to all items in that category.

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Targeting Fields

FieldDescriptionExample
Target PermissionsWhich permissions this policy applies todevices.read, integrations.execute
Target RolesWhich roles this policy applies toViewer, Analyst
Target Device NamesRegex patterns for device names.*prod.*, srv-db-.*
Target Device OSOperating system filter (case-insensitive)Windows, Ubuntu, Darwin, Amazon Linux
Target Integration NamesRegex patterns for integration names.*firewall.*, aws-.*
Target Integration BasesIntegration type/vendorFortigate, AWS, Palo Alto
Smart Visibility: In the policy form, device targeting fields only appear when device-related permissions are selected. Integration fields only appear when integration permissions are selected. This keeps the form clean and focused.

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Evaluation Flow

When a user makes a request, the system evaluates policies in this order:
1

RBAC Check

The system first verifies the user has the required permission through their assigned roles. If not, access is denied immediately — no policies are evaluated.
2

Policy Matching

The system finds all active security policies that match the request based on targeting (permissions, roles, device, integration). Policies are ordered by priority (highest first).
3

Condition Evaluation

For each matching policy, the system evaluates all conditions. All conditions within a policy must pass (AND logic).
4

Effect Application

  • Deny policy: If conditions are NOT met → access is blocked (HTTP 403).
  • Allow policy: If conditions ARE met → access is granted.
  • If no policies match or all pass → access follows the RBAC result.

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Real-World Examples

Goal: Restrict SOC Analyst access to business hours only.
SettingValue
NameSOC Business Hours
EffectDeny
Priority10
Target RolesAnalyst
Condition 1time_of_day between 08:00 and 18:00
Condition 2day_of_week in monday, tuesday, wednesday, thursday, friday
Result: Analysts can only access the platform Monday–Friday, 8 AM to 6 PM. Outside these times, all their requests return 403.
Goal: Require MFA for any action on production devices.
SettingValue
NameProduction MFA Required
EffectDeny
Priority20
Target Device Names.*prod.*
Conditionmfa_status equals true
Result: Any device whose name matches .*prod.* requires the user to have an active MFA session. Users without MFA are blocked.
Goal: Allow firewall integration management only from the corporate VPN.
SettingValue
NameVPN-Only Firewall Access
EffectDeny
Priority15
Target Permissionsintegrations.update, integrations.execute
Target Integration BasesFortigate, Palo Alto
Conditionsource_ip in 198.51.100.0/24
Result: Editing or executing commands on Fortigate and Palo Alto integrations is only allowed from the corporate VPN IP range (198.51.100.0/24). Access from other IPs is blocked.
Goal: External auditors (Viewer role) can only access the platform on weekdays.
SettingValue
NameViewer Weekdays Only
EffectDeny
Priority5
Target RolesViewer
Conditionday_of_week in monday, tuesday, wednesday, thursday, friday
Result: Users with the Viewer role are blocked on weekends. Other roles (Admin, Analyst) are unaffected.

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Next Steps

Available Conditions

Explore all six condition types with syntax, operators, and examples.

Managing Policies

Step-by-step guide to creating, editing, and organizing policies in the interface.