# Mainframe Security Assessment

> Use for mainframe, z/OS, RACF, ACF2, Top Secret, CICS, IMS, DB2, JCL, JES, APF libraries, USS, TN3270, privileged dataset, and legacy enterprise security assessment work.

- Skill: `26zl/mainframe-security-assessment` (Agent Skill)
- Install (CLI): `npx skillmds@latest add 26zl/mainframe-security-assessment`
- Raw SKILL.md: https://api.skillmd.com/api/skills/26zl/mainframe-security-assessment/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: 26zl (https://skillmd.com/u/26zl)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/26zl/mainframe-security-assessment

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# Mainframe security assessment

Use this skill when reviewing IBM z/OS or similar mainframe environments, identity controls, privileged datasets, transaction systems, and batch operations.

## Guardrails

- Treat production mainframes as safety-critical business systems. Avoid invasive testing unless explicitly approved.
- Prefer configuration review, evidence collection, and read-only queries.
- Coordinate with platform owners before touching RACF/ACF2/Top Secret policy, APF libraries, JES, CICS, or DB2 privileges.

## Workflow

1. Scope platform, security manager, LPARs, subsystems, network paths, and business-critical workloads.
2. Review identity and access:
   - privileged users and groups
   - dataset profiles and universal access
   - password/MFA/session policy
   - service IDs and stale accounts
3. Review system integrity:
   - APF-authorized libraries
   - program properties table
   - exits and started tasks
   - USS permissions
   - operator commands and console access
4. Review application surfaces:
   - CICS transactions
   - DB2 privileges
   - IMS regions
   - JCL libraries and scheduler access
   - TN3270 exposure and encryption
5. Produce a risk-ranked remediation plan with operational impact.

## Output pattern

| Area | Control weakness | Evidence needed | Business impact | Remediation | Change risk |
| --- | --- | --- | --- | --- | --- |