CVE-2019-19849

An issue was discovered in TYPO3 before 8.7.30, 9.x before 9.5.12, and 10.x before 10.2.2. It has been discovered that the classes QueryGenerator and QueryView are vulnerable to insecure deserialization. One exploitable scenario requires having the system extension ext:lowlevel (Backend Module: DB Check) installed, with a valid backend user who has administrator privileges. The other exploitable scenario requires having the system extension ext:sys_action installed, with a valid backend user who has limited privileges.

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

• https://review.typo3.org/q/%2522Resolves:+%252389005%2522+topic:security
• https://typo3.org/security/advisory/typo3-core-sa-2019-026/
• https://review.typo3.org/q/%2522Resolves:+%252389005%2522+topic:security
• https://typo3.org/security/advisory/typo3-core-sa-2019-026/