A Type Confusion vulnerability was found in Sambas mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets, one encoded data structure is a key-value style dictionary where the keys are character strings, and the values can be any of the supported types in the mdssvc protocol. Due to a lack of type checking in callers of the dalloc_value_for_key() function, which returns the object associated with a key, a caller may trigger a crash in talloc_get_size() when talloc detects that the passed-in pointer is not a valid talloc pointer. With an RPC worker process shared among multiple client connections, a malicious client or attacker can trigger a process crash in a shared RPC mdssvc worker process, affecting all other clients this worker serves.
The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Samba | Samba | * | 4.16.11 (excluding) |
| Samba | Samba | 4.17.0 (including) | 4.17.10 (excluding) |
| Samba | Samba | 4.18.0 (including) | 4.18.5 (excluding) |
When the product accesses the resource using an incompatible type, this could trigger logical errors because the resource does not have expected properties. In languages without memory safety, such as C and C++, type confusion can lead to out-of-bounds memory access. While this weakness is frequently associated with unions when parsing data with many different embedded object types in C, it can be present in any application that can interpret the same variable or memory location in multiple ways. This weakness is not unique to C and C++. For example, errors in PHP applications can be triggered by providing array parameters when scalars are expected, or vice versa. Languages such as Perl, which perform automatic conversion of a variable of one type when it is accessed as if it were another type, can also contain these issues.