CVE-2019-19470

Unsafe usage of .NET deserialization in Named Pipe message processing allows privilege escalation to NT AUTHORITYSYSTEM for a local attacker. Affected product is TinyWall, all versions up to and including 2.1.12. Fixed in version 2.1.13.

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://gist.github.com/pylorak/7df52c9325614676e07782dbe4e81582
• https://www.wilderssecurity.com/threads/beta-testing-tinywall.309739/page-62#post-2882843
• https://gist.github.com/pylorak/7df52c9325614676e07782dbe4e81582
• https://www.wilderssecurity.com/threads/beta-testing-tinywall.309739/page-62#post-2882843