The security toolkit built for 2026

Open-source web and network security toolkit. MIT licensed. Self-host first. Intercept & replay traffic, run the full active-testing battery, scan the network and correlate CVEs, and ship engagement reports — all without a license server phoning home.

v3.7.0 · MIT · macOS · Linux · Windows · ~14 MB

nullock — Proxy listening :8080
0 captured
#MethodHostPathStatusLenTime
Request

        
Response

        

Live capture, running locally. Click a row to inspect the raw exchange.


// what you get

Everything in the box. No add-on tax.

Intercept & edit

Pause any request or response, rewrite it inline, and forward. Full TLS interception with a CA you control.

Repeater

Send a captured request to Repeater, tweak the payload, fire it 1 or 1000 times. Diff responses side by side.

Scoped history

200k+ rows on a 16GB box. SQLite-backed, indexed and filterable by host, method, path, or status.

Match & replace

Rule-based rewriting on the wire. Regex headers and bodies in both directions without touching the client.

Extensions

Drop a single file into the extensions dir. Hook the request lifecycle in JavaScript. No marketplace gate.

Local first

Your captures never leave the machine. No telemetry, no account, no license server. Air-gap it if you want.

// honest comparison

How it stacks up

Three good tools. Here's where each one wins, no spin.

CapabilitynullockBurp Suitemitmproxy
LicenseMIT, freeCommercialMIT, free
Desktop GUI✓ nativeterminal / web
Repeater + diff✓ (Pro)manual
Scriptable extensions✓ JavaScript✓ Java✓ Py
History at 200k rows✓ SQLiteheavyin-memory
Passive detectors✓ 100+ kinds✓ ~70none
CWE / OWASP / CVSS tags✓ on every finding✓ (Pro)
CVE correlation✓ built-inadd-on
GraphQL attack probes + schema audit✓ 5 attacks + introspectionadd-on
DOM-XSS taint analysis✓ proxy-side✓ in-browser
Request chains (variable passing)macros only
JWT attack toolkit✓ coreadd-on
Hidden parameter mining✓ coreadd-on
IDOR / BOLA auto-detectionmanual
Mass-assignment scanner (API #6)manual
Active CORS exploitability✓ proves itpassive
JS endpoint + source-map reconsitemap only
Race-condition tester✓ coreTurbo extension
Verb-tampering auth bypass
SSTI detection + engine fingerprint✓ coremanual
Web cache poisoning (safe-confirm)✓ coreParam Miner add-on
Open redirect (resolved-host confirm)✓ coremanual
CSP audit (gadget-host aware)✓ corebasic header check
Secret scan in JS (masked)✓ coreadd-on
CRLF / response splitting (confirmed)✓ corepassive hint
Path traversal / LFI (content-confirmed)✓ coreadd-on
OS command injection (exec-confirmed)✓ coreadd-on
Reflected XSS (context-confirmed)✓ coreadd-on
SQL injection (error-based + DBMS fp)✓ coreadd-on
XXE (content-confirmed file read)✓ coreadd-on
NoSQL injection (operator differential)✓ coreadd-on
HTTP request smuggling (CL.TE/TE.CL)✓ coreextension
Service-version CVE scan (nmap-vulners)✓ core
Port-scan → findings + CVE bridge✓ core
Recon→vuln pipeline (point-at-host)✓ one commandmanual chaining
TLS/cert inspection (testssl-class)✓ core
Active tech fingerprint (WhatWeb-class)✓ corepassive
HTTP method / WebDAV / XST audit✓ corepassive
Subdomain takeover detection✓ coreadd-on
One-call host assessment✓ coremanual
Sensitive-file exposure (.git/.env/...)✓ coreadd-on
robots.txt / sitemap recon✓ corecrawl only
WAF / CDN detection (wafw00f-class)✓ core
Web cache deception✓ coremanual
One-command deep audit (whole battery)✓ audit allper-insertion config
HTML / Markdown engagement report✓ core✓ (Pro)
JSON master report (CI bundle)✓ coreEnterprise API
Host-centric asset inventory (risk-sorted)✓ coresite map only
CycloneDX SBOM export✓ core
Findings baseline / diff (re-test deltas)✓ coreEnterprise only
Security posture grade (A–F score)✓ core
OWASP Top-10 / compliance coverage✓ coreEnterprise only
Live CVE feed sync (runtime overlay)✓ coreadd-on
AI payload generation✓ local Ollama
Authorization tester✓ multi-user✓ (Pro)
Token randomness (Sequencer)✓ free✓ (Pro)
OAST / collab callbacks✓ self-host✓ (Pro, cloud)
OAST auto-correlation (confirmed SSRF)✓ free✓ (Pro)
DNS OAST sink (Log4Shell / blind exfil)✓ self-host✓ (Pro, cloud)
Telemetrynoneopt-outnone
Price to get started$0$475/yr$0

// 30-second quickstart

Install, capture, done

terminal
# grab the binary for your OS from Releases, then:
NullockApp --proxy-port=8080 --control-port=17777
# trust the generated CA · point your browser at 127.0.0.1:8080
nullock scope add 'https://target.example/*'
nullock scan target.example top100
# ─── running · findings streaming in ───

// roadmap

What's coming

building
Browser-driven DAST

Render SPAs in a headless browser to confirm DOM-XSS sinks in-page and crawl client-rendered routes.

building
HTTP/3 + QUIC capture

Decode QUIC streams with a local key log — detection already ships.

planned
Collaborative scopes

Share a read-only capture session over the LAN with a self-hosted relay.

planned
Signed & notarized installers

One-click first run — notarized macOS .dmg and signed Windows builds.

Free desktop. Paid hosting. No bait.

Pay for hosted services if you need them, or for support if you want a human on email.