Cross-Site Scripting in third party library mso/idna-convert
Make sure to not expose the vendor directory to the publicly accessible document root. In composer managed installation, make sure to configure a dedicated web folder. In general it is recommended to not expose the complete typo3_src sources folder in the document root.
The TYPO3 backend module stores the username of an authenticated backend user in its cache files. By guessing the file path to the cache files it is possible to receive valid backend usernames.
Failing to properly escape user input, the frontend login component is vulnerable to SQL Injection. A valid frontend user account is needed to exploit this vulnerability.
Extbase request handling fails to implement a proper access check for requested controller/ action combinations, which makes it possible for an attacker to execute arbitrary Extbase actions by crafting a special request. To successfully exploit this vulnerability, an attacker must have access to at least one Extbase plugin or module action in a TYPO3 installation. The missing access check inevitably leads to information disclosure or remote code execution, depending on the action that an attacker is able to execute.
Failing to properly validate incoming import data, the Import/Export component is susceptible to insecure unserialize. To exploit this vulnerability a valid backend user account is needed.
Failing to properly encode user input, some backend components are vulnerable to Cross-Site Scripting. A valid backend user account is needed to exploit this vulnerability.
The workspace/ version preview link created by a privileged (backend) user could be abused to obtain certain editing permission, if the admin panel is configured to be shown. A valid preview link is required to exploit this vulnerability.
Failing to properly encode user input, some backend components are vulnerable to Cross-Site Scripting. A valid backend user account is needed to exploit this vulnerability.
The default authentication service misses to invalidate empty strings as password. Therefore it is possible to authenticate backend and frontend users without password set in the database.
Note: TYPO3 does not allow to create user accounts without a password. Your TYPO3 installation might only be affected if there is a third party component creating user accounts without password by directly manipulating the database.
Failing to properly validate user input, the form component is susceptible to Arbitrary File Disclosure. A valid backend user account is needed to exploit this vulnerability. Only forms are vulnerable, which contain upload fields.
Cross-Site Scripting (XSS) in TYPO3 component CSS styled content
Failing to properly encode user input, the CSS styled content component is susceptible to Cross-Site Scripting, allowing authenticated editors to inject arbitrary HTML or JavaScript.
XML External Entity (XXE) Processing in TYPO3 Core
All XML processing within the TYPO3 CMS are vulnerable to XEE processing. This can lead to load internal and/or external (file) content within an XML structure. Furthermore it is possible to inject arbitrary files for an XML Denial of Service attack. For more information on that topic see https://www.owasp.org/index.php/XML_External_Entity_(XXE)_Processing.
TYPO3 Cross-Site Scripting in legacy form component
Failing to sanitize content from editors, the legacy form component is susceptible to Cross-Site Scripting. A valid editor account with access to a form content element is required to exploit this vulnerability.
TYPO3 Cross-Site Scripting in link validator component
Failing to sanitize content from editors, the link validator component is susceptible to Cross-Site Scripting. A valid editor account with access to content which is scanned by the link validator component is required to exploit this vulnerability.
TYPO3 Multiple Cross-Site Scripting vulnerabilities in frontend
Failing to properly encode editor input, several frontend components are susceptible to Cross-Site Scripting, allowing authenticated editors to inject arbitrary HTML.
A flaw in the database escaping API results in a SQL injection vulnerability when extension dbal is enabled and configured for MySQL passthrough mode in its extension configuration. All queries which use the DatabaseConnection::sql_query are vulnerable, even if arguments were properly escaped with DatabaseConnection::quoteStr beforehand.
Cross-Site Scripting in TYPO3 component Indexed Search
Failing to properly encode editor input, the search result view of indexed_search is susceptible to Cross-Site Scripting, allowing authenticated editors to inject arbitrary HTML.