> ## Documentation Index
> Fetch the complete documentation index at: https://rootea.es/llms.txt
> Use this file to discover all available pages before exploring further.

# CORS (Cross-Origin Resource Sharing)

> Cross-platform resources for CORS (Cross-Origin Resource Sharing): curated HTB machines, PortSwigger labs and TryHackMe rooms with validated writeups and related skills.

# CORS (Cross-Origin Resource Sharing)

This page aggregates **cross-platform resources to practice CORS (Cross-Origin Resource Sharing)**: retired Hack The Box machines, PortSwigger Web Security Academy labs and TryHackMe rooms, plus curated resources (HackTricks, PortSwigger, etc.) and related skills.

## Curated resources

| Source      | Link                                                                                   |
| ----------- | -------------------------------------------------------------------------------------- |
| PortSwigger | [https://portswigger.net/web-security/cors](https://portswigger.net/web-security/cors) |

## PortSwigger labs practicing CORS (Cross-Origin Resource Sharing) (3)

| Lab                                                                                                         | Difficulty                                                 | Topic | Official                                                                             |
| ----------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------- | ----- | ------------------------------------------------------------------------------------ |
| [CORS vulnerability with basic origin reflection](/en/portswigger/labs/cors/basic-origin-reflection-attack) | <span className="dbadge dbadge-easy">APPRENTICE</span>     | CORS  | [Open](https://portswigger.net/web-security/cors/lab-basic-origin-reflection-attack) |
| [CORS vulnerability with trusted null origin](/en/portswigger/labs/cors/null-origin-whitelisted-attack)     | <span className="dbadge dbadge-easy">APPRENTICE</span>     | CORS  | [Open](https://portswigger.net/web-security/cors/lab-null-origin-whitelisted-attack) |
| [CORS vulnerability with trusted insecure protocols](/en/portswigger/labs/cors/breaking-https-attack)       | <span className="dbadge dbadge-medium">PRACTITIONER</span> | CORS  | [Open](https://portswigger.net/web-security/cors/lab-breaking-https-attack)          |

***

← [Back to the full glossary](/en/glossary)

<script type="application/ld+json">
  {`{"@context":"https://schema.org","@type":"DefinedTerm","name":"CORS (Cross-Origin Resource Sharing)","termCode":"cors","inLanguage":"en","url":"https://rootea.es/en/skills/cors","inDefinedTermSet":{"@type":"DefinedTermSet","name":"Tactical pentesting glossary","url":"https://rootea.es/en/glossary"}}`}
</script>

*Last updated: 2026-05-08*