critical9.8

CVE-2022-23535

LiteDB may deserialize bad JSON on object type using _type

Impact

### Impact LiteDB use a special field in JSON documents to cast diferent types from `BsonDocument` do POCO classes. When instance of an object are not the same of class, `BsonMapper` use a special field `_type` string info with full class name with assembly to be loaded and fit in your model. If your end-user can send to your app a plain JSON string, deserialization can load an unsafe object to fit in your model. ### Patches Version >= 5.0.13 add some basic fixes to avoid this, but is not 100% guaranteed when using `Object` type Next major version will contains a allow-list to select what king of Assembly can be loaded ### Workarounds - Avoid users send to your app a JSON string to be direct insert/update into database - Avoid use classes with `Object` type - try use an interface when possible If your app send a plain JSON string to be insert/update into database, prefer this: ``` // Bad public class Customer { public int Id { get; set; } public string Name { get; set; } public Object AnyData { get; set; } // <= Avoid use `Object` base type } // Good public class Customer { public int Id { get; set; } public string Name { get; set; } public IDictionary<string, string> AnyData { get; set; } // Will accept only key/value strings } ``` ### References See this workaround fix on this commit: https://github.com/mbdavid/LiteDB/commit/4382ff4dd0dd8b8b16a4e37dfd29727c5f70f93f

Affected packages

Ecosystem	Package	Affected	Fixed in
nuget	`LiteDB`	< 5.0.13	5.0.13

Affected products

Vendor	Product	Affected versions
Litedb	Litedb	before 5.0.13

Weakness classification

CWE-502