The BSON encoder in the MongoDB PHP Driver does not check some return values after a document exceeds libbson's size limit. This can leave the encoder in an invalid state. An unauthenticated actor who can cause an affected application to encode an unusually large data structure can terminate the PHP worker or cause the resulting document to omit fields. No MongoDB server connection or database authentication is required.

Impact Passing untrusted input as part of a database or collection name may result in targeting a different database or collection than specified.

Patches Fixed in PHP library 1.21.4 and 2.4.1.

Workarounds Validate database and collection names prior to passing into APIs.

Deserialization of untrusted data in the command monitoring support of the MongoDB PHP Driver can cause class names embedded in document content to be honored when the driver builds monitoring event objects. When an application registers a command monitoring subscriber and includes untrusted data in a database operation, an unauthenticated party who controls that data may cause an application class implementing the driver's persistable interface to be instantiated and its unserialization method invoked with the supplied data. The resulting impact depends on the classes available in the application.

Incorrect validation of files loaded from a local untrusted directory may allow local privilege escalation if the underlying operating systems is Windows. This may result in the application executing arbitrary behaviour determined by the contents of untrusted files. This issue affects MongoDB Server v5.0 versions prior to 5.0.27, MongoDB Server v6.0 versions prior to 6.0.16, MongoDB Server v7.0 versions prior to 7.0.12, MongoDB Server v7.3 versions prior 7.3.3, MongoDB C Driver versions prior to 1.26.2 and MongoDB PHP Driver versions prior to 1.18.1.

Required Configuration:

Only environments with Windows as the underlying operating system is affected by this issue