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A SQL Injection vulnerability exists in MyBB before version 1.8.26, where theme properties included in theme XML files are not properly sanitized before being used in SQL queries. This allows an attacker to inject arbitrary SQL commands via crafted theme XML files.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository contains a working exploit for MyBB forum software, targeting CVE-2021-27889 (XSS) and CVE-2021-27890 (SQLi/RCE). The exploit is composed of two main files: '1.js' (JavaScript) and 'attack_listen.py' (Python). The attack flow is as follows: 1. The attacker injects a malicious JavaScript payload into a forum post or message, exploiting the XSS vulnerability (CVE-2021-27889). This payload loads '1.js' from the attacker's server when viewed by an admin. 2. '1.js' automates a series of actions in the admin's browser: it retrieves necessary tokens, imports a malicious theme containing a PHP webshell via SQL injection (CVE-2021-27890), sets the malicious theme as default, triggers the webshell, and then cleans up traces by deleting the theme and restoring the original state. 3. The webshell is written to 'cache/evil.php' on the target server, allowing the attacker to execute arbitrary PHP code via HTTP requests. 4. Upon successful exploitation, '1.js' notifies the attacker by making a request to 'http://192.168.92.165:8080/attack_success'. 5. 'attack_listen.py' is a simple Python script that listens for this callback, confirming the attack's success and providing the shell URL. The repository is operational and provides a full attack chain from XSS to RCE, including cleanup and notification. The endpoints and IPs are hardcoded for demonstration and should be changed by the user. The exploit is not part of a framework and is a standalone proof-of-concept with operational capabilities.
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