Managing Nuclei

---
name: managing-nuclei
description: |
  Use when working with Nuclei — projectDiscovery Nuclei vulnerability scanner
  for template-based scanning of web applications, networks, and cloud services.
  Covers scan execution, template management, result analysis, severity
  tracking, and integration with ProjectDiscovery Cloud. Use when running
  vulnerability scans, reviewing scan findings, managing nuclei templates, or
  analyzing scan results across targets.
connection_type: nuclei
preload: false
---

# Nuclei Management Skill

Manage and analyze Nuclei vulnerability scans, templates, findings, and scan configurations.

## CLI Conventions

### Authentication
For ProjectDiscovery Cloud Platform, use `Authorization: $PDCP_API_KEY`. For local CLI, no authentication needed.

### CLI Tool
`nuclei` (local) or ProjectDiscovery Cloud API at `https://cloud.projectdiscovery.io/api/v1`

### Core Helper Functions

```bash
#!/bin/bash

# Local nuclei scan
nuclei_scan() {
    local target="$1"
    local extra_args="${2:-}"
    nuclei -target "$target" -json -silent $extra_args 2>/dev/null
}

# ProjectDiscovery Cloud API
pdcp_api() {
    local method="$1"
    local endpoint="$2"
    local data="${3:-}"
    local base="https://cloud.projectdiscovery.io/api/v1"

    if [ -n "$data" ]; then
        curl -s -X "$method" \
            -H "Authorization: $PDCP_API_KEY" \
            -H "Content-Type: application/json" \
            "${base}${endpoint}" \
            -d "$data"
    else
        curl -s -X "$method" \
            -H "Authorization: $PDCP_API_KEY" \
            -H "Content-Type: application/json" \
            "${base}${endpoint}"
    fi
}
```

## Output Rules
- **TOKEN EFFICIENCY**: Extract only needed fields with `jq`
- Target <=50 lines per script output
- Never dump full scan output

## Discovery Phase

```bash
#!/bin/bash
echo "=== Nuclei Version ==="
nuclei -version 2>&1 | head -1

echo ""
echo "=== Template Stats ==="
nuclei -tl -silent 2>/dev/null | wc -l | xargs -I{} echo "Total templates: {}"

echo ""
echo "=== Templates by Severity ==="
for sev in critical high medium low info; do
    COUNT=$(nuclei -tl -silent -severity $sev 2>/dev/null | wc -l)
    echo "$sev: $COUNT"
done

echo ""
echo "=== Recent Scan Results (Cloud) ==="
pdcp_api GET "/scans?limit=5" \
    | jq -r '.data[]? | "\(.created_at[0:16])\t\(.status)\t\(.target_count) targets\t\(.finding_count) findings"' | column -t 2>/dev/null
```

## Analysis Phase

### Scan Results

```bash
#!/bin/bash
TARGET="${1:?Target URL or file required}"

echo "=== Running Targeted Scan ==="
nuclei -target "$TARGET" -json -silent -severity critical,high 2>/dev/null \
    | jq -r '"\(.info.severity)\t\(.template-id)\t\(.matched-at[0:50])\t\(.info.name[0:40])"' \
    | column -t | head -20

echo ""
echo "=== Finding Summary ==="
nuclei -target "$TARGET" -json -silent 2>/dev/null \
    | jq -r '.info.severity' | sort | uniq -c | sort -rn
```

### Template Management

```bash
#!/bin/bash
echo "=== Templates by Type ==="
for type in http dns file network; do
    COUNT=$(nuclei -tl -silent -type $type 2>/dev/null | wc -l)
    echo "$type: $COUNT"
done

echo ""
echo "=== CVE Templates (recent) ==="
nuclei -tl -silent -tags cve 2>/dev/null | tail -15

echo ""
echo "=== Template Update ==="
nuclei -update-templates 2>&1 | tail -5
```

### Cloud Platform Results

```bash
#!/bin/bash
echo "=== Scan History ==="
pdcp_api GET "/scans?limit=10" \
    | jq -r '.data[]? | "\(.created_at[0:16])\t\(.status)\ttargets:\(.target_count)\tfindings:\(.finding_count)"' | column -t

echo ""
echo "=== Findings by Severity ==="
pdcp_api GET "/findings?limit=1" \
    | jq '{total: .total}' 2>/dev/null

for sev in critical high medium low; do
    COUNT=$(pdcp_api GET "/findings?severity=${sev}&limit=1" | jq '.total // 0')
    echo "$sev: $COUNT"
done

echo ""
echo "=== Top Findings ==="
pdcp_api GET "/findings?severity=critical,high&limit=15" \
    | jq -r '.data[]? | "\(.severity)\t\(.template_id)\t\(.host[0:40])"' | column -t
```

## Output Format

Present results as a structured report:
```
Managing Nuclei 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

- **Rate limiting targets**: Always use `-rate-limit` flag to avoid overwhelming targets
- **Template updates**: Run `nuclei -update-templates` regularly for latest CVE checks
- **JSON output**: Use `-json` flag for parseable output, `-silent` to suppress banner
- **Severity filtering**: Use `-severity critical,high` to focus on important findings
- **Scan scope**: Nuclei can be aggressive -- always get authorization before scanning
- **Output size**: Full scans generate massive output -- always filter by severity