nuclei-index

nuclei-index

Map CVE IDs → your local nuclei-templates and get back a runnable, rate-limited nuclei command.

Vulnerability intel tells you what is exploitable on a target. nuclei-index hands you the firing pin: the exact nuclei invocation to verify it. It indexes a local nuclei-templates checkout by CVE, caches the result, and bridges "CVE-X applies" → "run this".

• Zero dependencies. Pure standard-library Python (≥3.9). No YAML parser, no network calls.
• Fast. Builds an on-disk index once and reuses it until your templates change.
• Scriptable. Clean importable API + --json output to wire into other tooling.

Install

# from GitHub:
pip install git+https://github.com/sonnycroco/nuclei-index

# or from a local clone:
git clone https://github.com/sonnycroco/nuclei-index
pip install ./nuclei-index

You also need a local nuclei-templates checkout. If you run nuclei, you already have one:

nuclei -update-templates

nuclei-index looks for templates in (first match wins):

• $NUCLEI_TEMPLATES
• ~/nuclei-templates
• ~/.local/nuclei-templates
• ~/.config/nuclei/templates

Usage

# Look up a CVE and get the command(s) to run
$ nuclei-index --cve CVE-2021-44228 --host https://target.example

[CVE-2021-44228] 2 template(s):
  - CVE-2021-44228  (critical)  Apache Log4j RCE (Log4Shell)
    /home/you/nuclei-templates/http/cves/2021/CVE-2021-44228.yaml
  - ...

  Run (rate-limited, authorized hosts only):
    nuclei -id CVE-2021-44228 -u https://target.example -rl 20 -timeout 10

# Emit `nuclei -t <path>` form (faster — skips loading the whole template set)
$ nuclei-index --cve CVE-2021-44228 --host https://target.example --by-path

# Machine-readable
$ nuclei-index --cve CVE-2021-44228 --json
{"cve": "CVE-2021-44228", "templates": [...], "commands": [...]}

# Index stats / force a rebuild
$ nuclei-index --stats
$ nuclei-index --rebuild

The index is cached at $XDG_CACHE_HOME/nuclei-index/ (default ~/.cache/nuclei-index/) and refreshed automatically when CVE templates are added or removed under any cves/ directory. The freshness check is a cheap signal over those directories — their modification times and year-subdir listings — so a clean run never has to re-scan every template to confirm the cache is current. It can't see two things on its own: an edit made in place to an existing template (filename and directory unchanged), or a CVE template dropped outside a cves/ directory. Run --rebuild to force a full re-scan in those cases.

As a library

import nuclei_index as ni

ni.templates_for_cve("CVE-2021-44228")
# [{'cve': 'CVE-2021-44228', 'id': 'CVE-2021-44228',
#   'path': 'http/cves/2021/CVE-2021-44228.yaml',
#   'name': 'Apache Log4j RCE', 'severity': 'critical',
#   'suspicious': False}, ...]

ni.runnable_cmd("CVE-2021-44228", "https://target.example", rate=20)
# 'nuclei -id CVE-2021-44228 -u https://target.example -rl 20 -timeout 10'

ni.runnable_cmds("CVE-2021-44228", "https://target.example")  # every match

Templates for a CVE are returned highest-severity first; runnable_cmd picks that top one, runnable_cmds returns all of them.

Responsible use

This tool only constructs commands — it never scans anything itself. The emitted nuclei commands are rate-limited by default. Only run them against hosts you are authorized to test.

Development

pip install -e ".[dev]"
pytest

The test suite builds a throwaway fake templates tree — it needs neither a real nuclei install nor your templates.

License

Apache-2.0.