Managing Tenable

---
name: managing-tenable
description: |
  Use when working with Tenable — tenable.io vulnerability management, asset
  discovery, scan orchestration, and risk-based prioritization. Covers
  vulnerability exports, asset inventory, VPR scoring, plugin analysis, scan
  scheduling, and compliance auditing. Use when reviewing vulnerability
  findings, analyzing asset exposure, prioritizing remediation efforts, or
  managing Tenable scan configurations.
connection_type: tenable
preload: false
---

# Tenable.io Management Skill

Manage and analyze Tenable.io vulnerabilities, assets, scans, and risk prioritization.

## API Conventions

### Authentication
All API calls use `X-ApiKeys: accessKey=$TENABLE_ACCESS_KEY;secretKey=$TENABLE_SECRET_KEY` -- injected automatically. Never hardcode keys.

### Base URL
`https://cloud.tenable.com`

### Core Helper Function

```bash
#!/bin/bash

tenable_api() {
    local method="$1"
    local endpoint="$2"
    local data="${3:-}"

    if [ -n "$data" ]; then
        curl -s -X "$method" \
            -H "X-ApiKeys: accessKey=$TENABLE_ACCESS_KEY;secretKey=$TENABLE_SECRET_KEY" \
            -H "Content-Type: application/json" \
            "https://cloud.tenable.com${endpoint}" \
            -d "$data"
    else
        curl -s -X "$method" \
            -H "X-ApiKeys: accessKey=$TENABLE_ACCESS_KEY;secretKey=$TENABLE_SECRET_KEY" \
            -H "Content-Type: application/json" \
            "https://cloud.tenable.com${endpoint}"
    fi
}
```

## Output Rules
- **TOKEN EFFICIENCY**: Extract only needed fields with `jq`
- Target <=50 lines per script output
- Always filter by relevant time range to avoid huge response sets
- Never dump full API responses

## Discovery Phase

```bash
#!/bin/bash
echo "=== Asset Count ==="
tenable_api GET "/assets" | jq '"Total assets: \(.assets | length)"' -r

echo ""
echo "=== Scan Summary ==="
tenable_api GET "/scans" | jq '{total_scans: (.scans | length), running: ([.scans[] | select(.status == "running")] | length)}'

echo ""
echo "=== Scanner Status ==="
tenable_api GET "/scanners" | jq -r '.scanners[] | "\(.name)\t\(.status)\t\(.type)"' | column -t | head -10
```

## Analysis Phase

### Vulnerability Overview

```bash
#!/bin/bash
echo "=== Vulnerability Counts by Severity ==="
tenable_api GET "/workbenches/vulnerabilities?date_range=30&filter.0.filter=severity&filter.0.quality=eq&filter.0.value=Critical" \
    | jq '"Critical: \(.total_vulnerability_count)"' -r
tenable_api GET "/workbenches/vulnerabilities?date_range=30&filter.0.filter=severity&filter.0.quality=eq&filter.0.value=High" \
    | jq '"High: \(.total_vulnerability_count)"' -r

echo ""
echo "=== Top Vulnerabilities by VPR ==="
tenable_api GET "/workbenches/vulnerabilities?date_range=30&sort=vpr_score:desc&limit=15" \
    | jq -r '.vulnerabilities[:15][] | "\(.vpr_score // "N/A")\t\(.severity_index)\t\(.plugin_name[0:60])"' \
    | column -t

echo ""
echo "=== Exploitable Vulnerabilities ==="
tenable_api GET "/workbenches/vulnerabilities?date_range=30&filter.0.filter=exploit_available&filter.0.quality=eq&filter.0.value=true&limit=10" \
    | jq -r '.vulnerabilities[:10][] | "\(.severity_index)\tVPR:\(.vpr_score // "N/A")\t\(.plugin_name[0:60])"' | column -t
```

### Asset Risk Analysis

```bash
#!/bin/bash
echo "=== Highest Risk Assets (by ACR) ==="
tenable_api GET "/assets?limit=15&sort=acr_score:desc" \
    | jq -r '.assets[:15][] | "\(.acr_score // "N/A")\t\(.ipv4 // [] | join(","))\t\(.fqdn // [] | .[0] // "N/A")\t\(.operating_system // [] | .[0] // "Unknown" | .[0:30])"' \
    | column -t

echo ""
echo "=== Assets Not Scanned (>30 days) ==="
CUTOFF=$(date -u -v-30d +%Y-%m-%d)
tenable_api GET "/assets?limit=500" \
    | jq -r --arg cutoff "$CUTOFF" '[.assets[] | select(.last_authenticated_scan_date != null and .last_authenticated_scan_date < $cutoff)] | length | "Assets stale >30 days: \(.)"'
```

### Scan Management

```bash
#!/bin/bash
echo "=== Recent Scan Results ==="
tenable_api GET "/scans" \
    | jq -r '.scans[] | select(.status == "completed") | "\(.last_modification_date | todate[0:16])\t\(.name[0:40])\thosts:\(.hostcount)"' \
    | sort -r | head -15 | column -t

echo ""
echo "=== Running Scans ==="
tenable_api GET "/scans" \
    | jq -r '.scans[] | select(.status == "running") | "\(.name[0:40])\t\(.status)\thosts:\(.hostcount)"' | column -t
```

## Output Format

Present results as a structured report:
```
Managing Tenable Report
═══════════════════════
Resources discovered: [count]

Resource       Status    Key Metric    Issues
──────────────────────────────────────────────
[name]         [ok/warn] [value]       [findings]

Summary: [total] resources | [ok] healthy | [warn] warnings | [crit] critical
Action Items: [list of prioritized findings]
```

Target ≤50 lines of output. Use tables for multi-resource comparisons.

## Anti-Hallucination Rules

1. **NEVER assume resource names** — always discover via CLI/API in Phase 1 before referencing in Phase 2.
2. **NEVER fabricate metric names or dimensions** — verify against the service documentation or `--help` output.
3. **NEVER mix CLI commands between service versions** — confirm which version/API you are targeting.
4. **ALWAYS use the discovery → verify → analyze chain** — every resource referenced must have been discovered first.
5. **ALWAYS handle empty results gracefully** — an empty response is valid data, not an error to retry.

## Counter-Rationalizations

| Shortcut | Counter | Why |
|----------|---------|-----|
| "I'll skip discovery and check known resources" | Always run Phase 1 discovery first | Resource names change, new resources appear — assumed names cause errors |
| "The user only asked for a quick check" | Follow the full discovery → analysis flow | Quick checks miss critical issues; structured analysis catches silent failures |
| "Default configuration is probably fine" | Audit configuration explicitly | Defaults often leave logging, security, and optimization features disabled |
| "Metrics aren't needed for this" | Always check relevant metrics when available | API/CLI responses show current state; metrics reveal trends and intermittent issues |
| "I don't have access to that" | Try the command and report the actual error | Assumed permission failures prevent useful investigation; actual errors are informative |

## Common Pitfalls

- **Export API for large datasets**: Use `/vulns/export` and `/assets/export` for bulk data -- workbench APIs are for summaries
- **VPR vs CVSS**: Tenable prioritizes by VPR (Vulnerability Priority Rating) over CVSS
- **Rate limits**: 40 requests/second burst, sustained varies by license
- **Date formats**: Epoch timestamps in many responses -- convert with `todate` in jq
- **ACR/AES scores**: Asset Criticality Rating and Asset Exposure Score require Lumin license