I am currently working on getting better code reviews considering I am doing whitebox testing on a regular basis now. This will mostly be a dump of my notes as I research new things and will grow over time. 
<h1 id="heading-php">PHP</h1>
<ol>
<li><code>in_array</code></li>
</ol>
This PHP function is vulnerable to type juggling considering it may use loose comparisons if the function is used incorrectly.
Vulnerable code:
<pre><code>$values = array("naruto","sasuke","rock lee","gaara");
var_dump(in_array(0, $values));
</code></pre>Output:
<pre><code>bool(true)
</code></pre>This is obviously not the case considering 0 is not in the array, so a third parameter should be added to the function so that is uses strict comparisons.
Secure code:
<pre><code>$values = array("naruto","sasuke","rock lee","gaara");
var_dump(in_array(0, $values, true));
</code></pre>Output:
<pre><code>bool(false)
</code></pre><h1 id="heading-java">Java</h1>
<ol>
<li><code>MessageDigest hasher = MessageDigest.getInstance("SHA-256");</code></li>
</ol>
Whenever <code>SHA-256</code> is used by itself without an <code>HMAC</code>, it is vulnerable to a length extension vulnerability. If you know one hash, you can create new hashes without knowing the secret by adding data to the digest.

I am currently working on getting better code reviews considering I am doing whitebox testing on a regular basis now. This will mostly be a dump of my notes as I research new things and will grow over time. 

# PHP
1. `in_array`

This PHP function is vulnerable to type juggling considering it may use loose comparisons if the function is used incorrectly.

**Vulnerable code**:
```
$values = array("naruto","sasuke","rock lee","gaara");
var_dump(in_array(0, $values));
```
**Output**:
```
bool(true)
```
This is obviously not the case considering 0 is not in the array, so a third parameter should be added to the function so that is uses strict comparisons.

**Secure code**:
```
$values = array("naruto","sasuke","rock lee","gaara");
var_dump(in_array(0, $values, true));
```
**Output**:
```
bool(false)
```
# Java
1. `MessageDigest hasher = MessageDigest.getInstance("SHA-256");`

Whenever `SHA-256` is used by itself without an `HMAC`, it is vulnerable to a length extension vulnerability. If you know one hash, you can create new hashes without knowing the secret by adding data to the digest.



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