Vulnerability scanner based on simple YAML based DSL
Fast and customisable vulnerability scanner based on simple YAML based DSL.
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Nuclei is used to send requests across targets based on a template, leading to zero false positives and providing fast scanning on a large number of hosts. Nuclei offers scanning for a variety of protocols, including TCP, DNS, HTTP, SSL, File, Whois, Websocket, Headless etc. With powerful and flexible templating, Nuclei can be used to model all kinds of security checks.
We have a dedicated repository that houses various type of vulnerability templates contributed by more than 300 security researchers and engineers.
How it works
Nuclei requires go1.17 to install successfully. Run the following command to install the latest version -
go install -v github.com/projectdiscovery/nuclei/v2/cmd/nuclei@latest
More installation methods can be found here.
Nuclei has built-in support for automatic template download/update as default since version v2.5.2. Nuclei-Templates project provides a community-contributed list of ready-to-use templates that is constantly updated.
You may still use the
update-templates flag to update the nuclei templates at any time; You can write your own checks for your individual workflow and needs following Nuclei's templating guide.
The YAML DSL reference syntax is available here.
This will display help for the tool. Here are all the switches it supports.
Nuclei is a fast, template based vulnerability scanner focusing on extensive configurability, massive extensibility and ease of use.Running Nuclei
Usage: nuclei [flags]
Flags: TARGET: -u, -target string target URLs/hosts to scan -l, -list string path to file containing a list of target URLs/hosts to scan (one per line) -resume string Resume scan using resume.cfg (clustering will be disabled)
TEMPLATES: -nt, -new-templates run only new templates added in latest nuclei-templates release -ntv, -new-templates-version string run new templates added in specific version -as, -automatic-scan automatic web scan using wappalyzer technology detection to tags mapping -t, -templates string list of template or template directory to run (comma-separated, file) -tu, -template-url string list of template urls to run (comma-separated, file) -w, -workflows string list of workflow or workflow directory to run (comma-separated, file) -wu, -workflow-url string list of workflow urls to run (comma-separated, file) -validate validate the passed templates to nuclei -nss, -no-strict-syntax Disable strict syntax check on templates -tl list all available templates
FILTERING: -a, -author string templates to run based on authors (comma-separated, file) -tags string templates to run based on tags (comma-separated, file) -etags, -exclude-tags string templates to exclude based on tags (comma-separated, file) -itags, -include-tags string tags to be executed even if they are excluded either by default or configuration -id, -template-id string templates to run based on template ids (comma-separated, file) -eid, -exclude-id string templates to exclude based on template ids (comma-separated, file) -it, -include-templates string templates to be executed even if they are excluded either by default or configuration -et, -exclude-templates string template or template directory to exclude (comma-separated, file) -em, -exclude-matchers string template matchers to exclude in result -s, -severity value templates to run based on severity. Possible values: info, low, medium, high, critical, unknown -es, -exclude-severity value templates to exclude based on severity. Possible values: info, low, medium, high, critical, unknown -pt, -type value templates to run based on protocol type. Possible values: dns, file, http, headless, network, workflow, ssl, websocket, whois -ept, -exclude-type value templates to exclude based on protocol type. Possible values: dns, file, http, headless, network, workflow, ssl, websocket, whois
OUTPUT: -o, -output string output file to write found issues/vulnerabilities -sresp, -store-resp store all request/response passed through nuclei to output directory -srd, -store-resp-dir string store all request/response passed through nuclei to custom directory (default "output") -silent display findings only -nc, -no-color disable output content coloring (ANSI escape codes) -json write output in JSONL(ines) format -irr, -include-rr include request/response pairs in the JSONL output (for findings only) -nm, -no-meta disable printing result metadata in cli output -nts, -no-timestamp disable printing timestamp in cli output -rdb, -report-db string nuclei reporting database (always use this to persist report data) -ms, -matcher-status display match failure status -me, -markdown-export string directory to export results in markdown format -se, -sarif-export string file to export results in SARIF format
CONFIGURATIONS: -config string path to the nuclei configuration file -fr, -follow-redirects enable following redirects for http templates -mr, -max-redirects int max number of redirects to follow for http templates (default 10) -dr, -disable-redirects disable redirects for http templates -rc, -report-config string nuclei reporting module configuration file -H, -header string custom header/cookie to include in all http request in header:value format (cli, file) -V, -var value custom vars in key=value format -r, -resolvers string file containing resolver list for nuclei -sr, -system-resolvers use system DNS resolving as error fallback -passive enable passive HTTP response processing mode -ev, -env-vars enable environment variables to be used in template -cc, -client-cert string client certificate file (PEM-encoded) used for authenticating against scanned hosts -ck, -client-key string client key file (PEM-encoded) used for authenticating against scanned hosts -ca, -client-ca string client certificate authority file (PEM-encoded) used for authenticating against scanned hosts -sml, -show-match-line show match lines for file templates, works with extractors only -ztls use ztls library with autofallback to standard one for tls13 -sni string tls sni hostname to use (default: input domain name)
INTERACTSH: -iserver, -interactsh-server string interactsh server url for self-hosted instance (default: oast.pro,oast.live,oast.site,oast.online,oast.fun,oast.me) -itoken, -interactsh-token string authentication token for self-hosted interactsh server -interactions-cache-size int number of requests to keep in the interactions cache (default 5000) -interactions-eviction int number of seconds to wait before evicting requests from cache (default 60) -interactions-poll-duration int number of seconds to wait before each interaction poll request (default 5) -interactions-cooldown-period int extra time for interaction polling before exiting (default 5) -ni, -no-interactsh disable interactsh server for OAST testing, exclude OAST based templates
RATE-LIMIT: -rl, -rate-limit int maximum number of requests to send per second (default 150) -rlm, -rate-limit-minute int maximum number of requests to send per minute -bs, -bulk-size int maximum number of hosts to be analyzed in parallel per template (default 25) -c, -concurrency int maximum number of templates to be executed in parallel (default 25) -hbs, -headless-bulk-size int maximum number of headless hosts to be analyzed in parallel per template (default 10) -headc, -headless-concurrency int maximum number of headless templates to be executed in parallel (default 10)
OPTIMIZATIONS: -timeout int time to wait in seconds before timeout (default 5) -retries int number of times to retry a failed request (default 1) -ldp, -leave-default-ports leave default HTTP/HTTPS ports (eg. host:80,host:443 -mhe, -max-host-error int max errors for a host before skipping from scan (default 30) -project use a project folder to avoid sending same request multiple times -project-path string set a specific project path -spm, -stop-at-first-path stop processing HTTP requests after the first match (may break template/workflow logic) -stream stream mode - start elaborating without sorting the input -irt, -input-read-timeout duration timeout on input read (default 3m0s) -no-stdin Disable Stdin processing
HEADLESS: -headless enable templates that require headless browser support (root user on linux will disable sandbox) -page-timeout int seconds to wait for each page in headless mode (default 20) -sb, -show-browser show the browser on the screen when running templates with headless mode -sc, -system-chrome Use local installed chrome browser instead of nuclei installed
DEBUG: -debug show all requests and responses -dreq, -debug-req show all sent requests -dresp, -debug-resp show all received responses -p, -proxy string list of http/socks5 proxy to use (comma separated or file input) -pi, -proxy-internal proxy all internal requests -tlog, -trace-log string file to write sent requests trace log -elog, -error-log string file to write sent requests error log -version show nuclei version -hm, -hang-monitor enable nuclei hang monitoring -v, -verbose show verbose output -vv display templates loaded for scan -ep, -enable-pprof enable pprof debugging server -tv, -templates-version shows the version of the installed nuclei-templates -hc, -health-check run diagnostic check up
UPDATE: -update update nuclei engine to the latest released version -ut, -update-templates update nuclei-templates to latest released version -ud, -update-directory string overwrite the default directory to install nuclei-templates -duc, -disable-update-check disable automatic nuclei/templates update check
STATISTICS: -stats display statistics about the running scan -sj, -stats-json write statistics data to an output file in JSONL(ines) format -si, -stats-interval int number of seconds to wait between showing a statistics update (default 5) -m, -metrics expose nuclei metrics on a port -mp, -metrics-port int port to expose nuclei metrics on (default 9092)
Scanning target domain with community-curated nuclei templates.
nuclei -u https://example.com
Scanning target URLs with community-curated nuclei templates.
nuclei -list urls.txt
http://example.com http://app.example.com http://test.example.com http://uat.example.com
More detailed examples of running nuclei can be found here.
For Security Engineers
Nuclei offers great number of features that are helpful for security engineers to customise workflow in their organisation. With the varieties of scan capabilities (like DNS, HTTP, TCP), security engineers can easily create their suite of custom checks with Nuclei.
For Bug Bounty hunters:
Nuclei allows you to customise your testing approach with your own suite of checks and easily run across your bug bounty programs. Moreover, Nuclei can be easily integrated into any continuous scanning workflow.
Please check our other open-source projects that might fit into your bug bounty workflow: github.com/projectdiscovery, we also host daily refresh of DNS data at Chaos.
For Penetration Testers:
Nuclei immensely improve how you approach security assessment by augmenting the manual, repetitive processes. Consultancies are already converting their manual assessment steps with Nuclei, it allows them to run set of their custom assessment approach across thousands of hosts in an automated manner.
Pen-testers get the full power of our public templates and customization capabilities to speed up their assessment process, and specifically with the regression cycle where you can easily verify the fix.
For Developers and Organisations
Nuclei is built with simplicity in mind, with the community backed templates by hundreds of security researchers, it allows you to stay updated with the latest security threats using continuous Nuclei scanning on the hosts. It is designed to be easily integrated into regression tests cycle, to verify the fixes and eliminate vulnerabilities from occurring in the future.
We have a discussion thread around this, there are already some bug bounty programs giving incentives to hackers on writing nuclei templates with every submission, that helps them to eliminate the vulnerability across all their assets, as well as to eliminate future risk in reappearing on productions. If you're interested in implementing it in your organisation, feel free to reach out to us. We will be more than happy to help you in the getting started process, or you can also post into the discussion thread for any help.
Thanks to all the amazing community contributors for sending PRs. Do also check out the below similar open-source projects that may fit in your workflow:
FFuF, Qsfuzz, Inception, Snallygaster, Gofingerprint, Sn1per, Google tsunami, Jaeles, ChopChop
Nuclei is distributed under MIT License
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