> For the complete documentation index, see [llms.txt](https://sec88.0x88.online/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sec88.0x88.online/web-appsec/features-abuse/captcha.md).

# CAPTCHA

* [ ] [**Captcha Bypass via response manipulation**](https://bugcrowd.com/disclosures/55b40919-2c02-402c-a2cc-7184349926d7/login-capctha-bypass)
* [ ] **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>
* [ ] Online Services to bypass captchas [Capsolver](https://www.capsolver.com)


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