Craft CMS vulnerable to stored XSS in breadcrumb list and title fields

Summary

Multiple Stored XSS can be triggered by the breadcrumb list and title fields with user input.

Details

1. In the /admin/categories page, category title isn't sanitized and triggered xss.
2. In the category edit page under the /admin/categories/, category title in breadcrumb list isn't sanitized and triggered xss.
3. In the /admin/entries page, entry title isn't sanitized and triggered xss.
4. In the entry edit page under the /admin/entries/, entry title in breadcrumb list isn't sanitized and triggered xss.
5. In the /admin/myaccount and pages under it, username or full name in breadcrumb list isn't sanitized and triggered xss.

Impact

Malicious users can tamper with the control panel.

PoC

1. In the /admin/categories page, category title isn't sanitized and triggered xss.

1. Access to the Settings -> Categories ( /admin/settings/categories )
2. Create new category group
3. Access to the Categories page ( /admin/categories/ )
4. Push the New category button
5. Input the Title column : xss<script>alert('xss')</script>
6. Push the Create Category or Save button
7. Access to the Categories page again and it triggers xss

2. In the category edit page under the /admin/categories/, category title in breadcrumb list isn't sanitized and triggered xss.

1. Access to the Settings -> Categories ( /admin/settings/categories )
2. Create new category group
3. Access to the Categories page ( /admin/categories/ )
4. Push the New category button
5. Input the Title column : xss<script>alert('xss')</script>
6. Push the Create Category or Save button
7. Access to the Category edit page again and it triggers xss

3. In the /admin/entries page, entry title isn't sanitized and triggered xss.

1. Access to the Settings -> Entry Types ( /admin/settings/entry-types )
2. Create new entry type
3. Access to the Settings -> Sections ( /admin/settings/sections )
4. Create new section
5. Access to the Entries page ( /admin/entries )
6. Push the New entry button
7. Input the Title column : xss<script>alert('xss')</script>
8. Push the Create entry or Save button
9. Access to the Entries page again and it triggers xss

4. In the entry edit page under the /admin/entries/, entry title in breadcrumb list isn't sanitized and triggered xss.

1. Access to the Settings -> Entry Types ( /admin/settings/entry-types )
2. Create new entry type
3. Access to the Settings -> Sections ( /admin/settings/sections )
4. Create new section
5. Access to the Entries page ( /admin/entries )
6. Push the New entry button
7. Input the Title column : xss<script>alert('xss')</script>
8. Push the Create entry or Save button
9. Access to the Entriy edit page again and it triggers xss