CVE-2021-42756 PoC — Fortinet FortiWeb 缓冲区错误漏洞

Source

https://github.com/3ndorph1n/CVE-2021-42756

Associated Vulnerability

Title:Fortinet FortiWeb 缓冲区错误漏洞 (CVE-2021-42756)
Description:Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.

Readme

# CVE-2021-42756

Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.

## Summary

When MitB protection is enabled, there is no limit to the length of the protected fields. This can lead to a stack overflow.

## PoC

Environment: FortiWeb 6.3.4

<img src="https://github.com/3ndorph1n/CVE-2021-42756/blob/main/poc.png" style="zoom: 67%;" />

## References

* [PSIRT Advisories | FortiGuard](https://www.fortiguard.com/psirt/FG-IR-21-186)

File Snapshot


 [4.0K]  /data/pocs/a89d1c9bb7320958349e3977425e55afd272ba43
├── [3.0K]  CVE-2021-42756.py
├── [125K]  poc.png
└── [ 706]  README.md

0 directories, 3 files

Shenlong Bot has cached this for you

Remarks

1. It is advised to access via the original source first.

2. Local POC snapshots are reserved for subscribers — if the original source is unavailable, the local mirror is part of the paid plan.

View subscription plans →

Goal Reached Thanks to every supporter — we hit 100%!