A vulnerability in the Snake YAML parser of Magnolia CMS v6.2.3 and below allows attackers to execute arbitrary code via a crafted YAML file.
Weakness
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Magnolia_cms | Magnolia-cms | * | 6.2.4 (excluding) |
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
References
- https://docs.magnolia-cms.com/product-docs/6.2/Releases/Release-notes-for-Magnolia-CMS-6.2.4.html#_security_advisory
- https://github.com/DrunkenShells/Disclosures/tree/master/CVE-2021-46364-YAML%20Deserialization-Magnolia%20CMS
- https://docs.magnolia-cms.com/product-docs/6.2/Releases/Release-notes-for-Magnolia-CMS-6.2.4.html#_security_advisory
- https://github.com/DrunkenShells/Disclosures/tree/master/CVE-2021-46364-YAML%20Deserialization-Magnolia%20CMS