CVE-2019-6340

Some field types do not properly sanitize data from non-form sources in Drupal 8.5.x before 8.5.11 and Drupal 8.6.x before 8.6.10. This can lead to arbitrary PHP code execution in some cases. A site is only affected by this if one of the following conditions is met: The site has the Drupal 8 core RESTful Web Services (rest) module enabled and allows PATCH or POST requests, or the site has another web services module enabled, like JSON:API in Drupal 8, or Services or RESTful Web Services in Drupal 7. (Note: The Drupal 7 Services module itself does not require an update at this time, but you should apply other contributed updates associated with this advisory if Services is in use.)

Weakness

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Software

Potential Mitigations

• Make fields transient to protect them from deserialization.
• An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/586.html

References

• http://www.securityfocus.com/bid/107106
• https://www.drupal.org/sa-core-2019-003
• https://www.exploit-db.com/exploits/46452/
• https://www.exploit-db.com/exploits/46459/
• https://www.exploit-db.com/exploits/46510/
• https://www.synology.com/security/advisory/Synology_SA_19_09
• http://www.securityfocus.com/bid/107106
• https://www.drupal.org/sa-core-2019-003
• https://www.exploit-db.com/exploits/46452/
• https://www.exploit-db.com/exploits/46459/
• https://www.exploit-db.com/exploits/46510/
• https://www.synology.com/security/advisory/Synology_SA_19_09