Authentication Bypass in TP-Link TL-WR840N/TL-WR841N CGI Interface
CVE-2018-11714 affects TP-Link TL-WR840N v5 00000005 0.9.1 3.16 v0001.0 Build 170608 Rel.58696n and TL-WR841N v13 00000013 0.9.1 4.16 v0001.0 Build 170622 Rel.64334n. The vulnerability is caused by improper session handling in the /cgi/ folder or a /cgi file. An attacker can bypass authentication for administrative actions by supplying a crafted HTTP Referer header set to "http://192.168.0.1/mainFrame.htm". Because the device trusts this header as if the request originated from an authenticated management context, requests to protected CGI endpoints can be processed without valid authentication.
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Exploits
1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
This repository contains a proof-of-concept exploit for CVE-2018-11714, targeting TP-Link TL-WR840N routers. The exploit leverages improper session handling in the router's web interface, specifically for endpoints under /cgi/. By sending a GET request to the /cgi/conf.bin endpoint with a crafted Referer header, the script bypasses authentication and downloads the router's configuration file. The script then processes the file by removing the first 144 bytes and decrypts the remainder using DES-ECB with a hardcoded key, outputting the plaintext configuration. The repository consists of a README.md describing the vulnerability and a single Python script (poc.py) implementing the exploit. The attack vector is network-based, requiring access to the router's web interface. Several file and HTTP endpoints are fingerprintable, including the specific URLs and output files used in the exploit process.
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Recent activity
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