AC 12 Session Termination

---
name: "AC-12_session-termination"
description: "Automatically terminate a user session after [organization-defined]."
category: "authorization"
version: "5.2.0"
author: "cyberstrike-official"
tags:
  - nist
  - sp800-53
  - rev5
  - ac-12
  - ac
tech_stack:
  - aws
  - azure
  - gcp
  - linux
  - windows
cwe_ids:
  - CWE-284
chains_with:
  - MA-4
  - SC-10
  - SC-23
prerequisites: []
severity_boost:
  MA-4: "Chain with MA-4 for comprehensive security coverage"
  SC-10: "Chain with SC-10 for comprehensive security coverage"
  SC-23: "Chain with SC-23 for comprehensive security coverage"
---

# AC-12 Session Termination

## High-Level Description

**Family:** Access Control (AC)
**Framework:** NIST SP 800-53 Rev 5

Session termination addresses the termination of user-initiated logical sessions (in contrast to [SC-10](#sc-10) , which addresses the termination of network connections associated with communications sessions (i.e., network disconnect)). A logical session (for local, network, and remote access) is initiated whenever a user (or process acting on behalf of a user) accesses an organizational system. Such user sessions can be terminated without terminating network sessions. Session termination ends all processes associated with a user’s logical session except for those processes that are specifically created by the user (i.e., session owner) to continue after the session is terminated. Conditions or trigger events that require automatic termination of the session include organization-defined periods of user inactivity, targeted responses to certain types of incidents, or time-of-day restrictions on system use.

## What to Check

- [ ] Verify AC-12 Session Termination is documented in SSP
- [ ] Confirm control is operating effectively
- [ ] Review evidence of continuous monitoring for AC-12

## How to Test

### Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for AC-12 implementation details. Verify the organization has documented how this control is satisfied.

### Step 2: Validate Implementation

```
# For cloud environments, use cloud-audit-mcp tools
# For on-premises, review system configurations directly

# Example: Check if account management policies exist
grep -r "account.management\|access.control" /etc/security/ 2>/dev/null
```

### Step 3: Test Operating Effectiveness

Verify the control is actively functioning, not just documented. Check logs, configurations, and operational evidence.

## Tools

| Tool            | Purpose                                | Usage                      |
| --------------- | -------------------------------------- | -------------------------- |
| cloud-audit-mcp | Check IAM policies and access controls | `cloud_audit_iam_policies` |
| hackbrowser | Test web application access controls   | `hackbrowser`        |

## Remediation Guide

### Control Statement

Automatically terminate a user session after [organization-defined].

### Implementation Guidance

Session termination addresses the termination of user-initiated logical sessions (in contrast to [SC-10](#sc-10) , which addresses the termination of network connections associated with communications sessions (i.e., network disconnect)). A logical session (for local, network, and remote access) is initiated whenever a user (or process acting on behalf of a user) accesses an organizational system. Such user sessions can be terminated without terminating network sessions. Session termination ends all processes associated with a user’s logical session except for those processes that are specifically created by the user (i.e., session owner) to continue after the session is terminated. Conditions or trigger events that require automatic termination of the session include organization-defined periods of user inactivity, targeted responses to certain types of incidents, or time-of-day restrictions on system use.

## Risk Assessment

| Finding                                   | Severity | Impact                    |
| ----------------------------------------- | -------- | ------------------------- |
| AC-12 Session Termination not implemented | High     | Access Control            |
| AC-12 partially implemented               | Medium   | Incomplete Access Control |

## CWE Categories

| CWE ID  | Title                   |
| ------- | ----------------------- |
| CWE-284 | Improper Access Control |

## References

- [NIST SP 800-53 Rev 5 - AC-12](https://csrc.nist.gov/projects/cprt/catalog#/cprt/framework/version/SP_800_53_5_1_1/home?element=ac-12)
- [NIST SP 800-53A Rev 5 (Assessment Procedures)](https://csrc.nist.gov/pubs/sp/800/53/a/r5/final)
- [NIST SP 800-53 Rev 5 Full Catalog](https://csrc.nist.gov/pubs/sp/800/53/r5/upd1/final)

## Checklist

- [ ] Control documented in SSP
- [ ] Implementation evidence collected
- [ ] Operating effectiveness validated
- [ ] Continuous monitoring in place
- [ ] Related controls (MA-4, SC-10, SC-23) reviewed