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# Captcha Bypass
To **automate** the **testing** of some functions of the server that allows user input it **could** be **needed** to **bypass** a **captcha** implementation. Therefore, try to test for these things:
* **Do not send the parameter** related to the captcha.
* Change from POST to GET or other HTTP Verbs
* Change to JSON or from JSON
* Send the **captcha parameter empty**.
* Check if the value of the captcha is **in the source code** of the page.
* Check if the value is **inside a cookie.**
* Try to use an **old captcha value**
* Check if you can use the **same** captcha **value** several times with **the same or different sessionID.**
* If the captcha consists on a **mathematical operation** try to **automate** the **calculation.**
* If the captcha consists of **read characters from an image**, check manually or with code **how many images** are being used and if only a **few images are being used, detect them by MD5.**
* Use an **OCR** ([https://github.com/tesseract-ocr/tesseract](https://github.com/tesseract-ocr/tesseract)).
Support HackTricks and get benefits!
- Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
- Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
- Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
- **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
- **Share your hacking tricks by submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**