GitHub Actions Self-Hosted Risk Audit

Audit GitHub Actions workflows that use self-hosted runners for untrusted trigger and credential-hardening risks.

Use this skill to flag risky workflow patterns when jobs run on self-hosted GitHub Actions runners.

What this skill does

• Scans workflow YAML files (.github/workflows/*.yml by default)
• Detects workflows that reference self-hosted runners
• Flags high-risk trigger combinations (pull_request_target, pull_request, issue_comment)
• Flags broad/self-hosted-only runner selection (no extra routing labels)
• Flags workflows with write-capable permissions in self-hosted contexts
• Flags actions/checkout steps that do not set persist-credentials: false
• Supports text/json output and CI fail gate

Inputs

Optional:

• WORKFLOW_GLOB (default: .github/workflows/*.y*ml)
• TOP_N (default: 20)
• OUTPUT_FORMAT (text or json, default: text)
• WARN_SCORE (default: 4)
• CRITICAL_SCORE (default: 8)
• WORKFLOW_FILE_MATCH / WORKFLOW_FILE_EXCLUDE (regex, optional)
• FAIL_ON_CRITICAL (0 or 1, default: 0)

Run

Text report:

WORKFLOW_GLOB='.github/workflows/*.yml' \
WARN_SCORE=4 \
CRITICAL_SCORE=8 \
bash skills/github-actions-self-hosted-risk-audit/scripts/self-hosted-risk-audit.sh

JSON output + fail gate:

WORKFLOW_GLOB='.github/workflows/*.y*ml' \
OUTPUT_FORMAT=json \
FAIL_ON_CRITICAL=1 \
bash skills/github-actions-self-hosted-risk-audit/scripts/self-hosted-risk-audit.sh

Run against bundled fixtures:

WORKFLOW_GLOB='skills/github-actions-self-hosted-risk-audit/fixtures/*.y*ml' \
bash skills/github-actions-self-hosted-risk-audit/scripts/self-hosted-risk-audit.sh

Output contract

• Exit 0 in reporting mode (default)
• Exit 1 when FAIL_ON_CRITICAL=1 and one or more workflows are critical
• Text mode prints summary + top flagged workflows
• JSON mode prints summary + flagged workflows + critical workflows