## FULL DISCLOSURE

#Product : Advanced Custom Fields
#Exploit Author : Rahul Pratap Singh
#Version : 4.4.7
#Home page Link :https://wordpress.org/plugins/advanced-custom-fields/
#Website : https://0x62626262.wordpress.com
#Linkedin : https://in.linkedin.com/in/rahulpratapsingh94
#Date : 1/5/2016

Authenticated XSS Vulnerability:

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Description:
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"type, label, name and field" parameters are not sanitized that leads to
XSS.

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Vulnerable Code:
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File Name: testfiles/advanced-custom-fields/core/views/meta_box_fields.php

Found at line:97
<div class="field field_type-<?php echo $field['type']; ?>
field_key-<?php echo $field['key']; ?>" data-type="<?php echo
$field['type']; ?>" data-id="<?php echo $field['key']; ?>">

Found at line:105
<a class="acf_edit_field row-title" title="<?php _e("Edit this
Field",'acf'); ?>" href="javascript:;"><?php echo $field['label']; ?></a>

Found at line:113
<td class="field_name"><?php echo $field['name']; ?></td>

Found at line:251
<input class="conditional-logic-field" type="hidden" name="fields[<?php
echo $field['key']; ?>][conditional_logic][rules][<?php echo $rule_i;
?>][field]" value="<?php echo $rule['field']; ?>" />

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POC:
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https://0x62626262.files.wordpress.com/2016/05/advanced-custom-fields-xss1.png

Fix:
No Fix

Vulnerability Disclosure Timeline:
→ April 24, 2016  – Contact to Vendor via support
→ April 24, 2015  – Vendor Response
→ April 27, 2015  – Bug Report Sent
→ April 27, 2015  – Vendor Response, asked for more info
→ April 28, 2015  – More info sent
→ April 29, 2015  – No fix. To do list for version 5.0

Pub Ref:
https://0x62626262.wordpress.com/2016/05/01/advanced-custom-fields-auth-xss-vulnerability