CWE-374: Passing Mutable Objects to an Untrusted Method | Glexia
CWE-374 (Passing Mutable Objects to an Untrusted Method) weakness overview with consequences, detection methods, mitigations, related CVEs and MITRE ATT&CK context.
Glexia's Take · Automated analysis
CWE-374: Passing Mutable Objects to an Untrusted Method
Passing Mutable Objects to an Untrusted Method represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Integrity: Modify Memory: Potentially data could be tampered with by another function which should not have been tampered with.
Developer Pattern
CWE-374 is the kind of defect developers can usually prevent with explicit validation, safer framework defaults, and tests that exercise hostile input or unsafe state transitions.
Automation confidence
high confidence from CWE-374, 4.20.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Official CWE Definition
CWE-374: Passing Mutable Objects to an Untrusted Method
The product sends non-cloned mutable data as an argument to a method or function.
The function or method that has been called can alter or delete the mutable data. This could violate assumptions that the calling function has made about its state. In situations where unknown code is called with references to mutable data, this external code could make changes to the data sent. If this data was not previously cloned, the modified data might not be valid in the context of execution.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- The following example demonstrates the weakness. In this example, bar and baz will be passed by reference to doOtherStuff() which may change them.
- In the following Java example, the BookStore class manages the sale of books in a bookstore, this class includes the member objects for the bookstore inventory and sales database manager classes. The BookStore class includes a method for updating the sales database and inventory when a book is sold. This method retrieves a Book object from the bookstore inventory object using the supplied ISBN number for the book class, then calls a method for the sales object to update the sales information and then calls a method for the inventory object to update inventory for the BookStore. However, in this example the Book object that is retrieved and passed to the method of the sales object could have its contents modified by the method. This could cause unexpected results when the book object is sent to the method for the inventory object to update the inventory.,In the Java programming language arguments to methods are passed by value, however in the case of objects a reference to the object is passed by value to the method. When an object reference is passed as a method argument a copy of the object reference is made within the method and therefore both references point to the same object. This allows the contents of the object to be modified by the method that holds the copy of the object reference. [REF-374],In this case the contents of the Book object could be modified by the method of the sales object prior to the call to update the inventory.,To prevent the contents of the Book object from being modified, a copy of the Book object should be made before the method call to the sales object. In the following example a copy of the Book object is made using the clone() method and the copy of the Book object is passed to the method of the sales object. This will prevent any changes being made to the original Book object.
Remediation
- Implementation: Pass in data which should not be altered as constant or immutable.
- Implementation: Clone all mutable data before passing it into an external function . This is the preferred mitigation. This way, regardless of what changes are made to the data, a valid copy is retained for use by the class.
Detection
- Code review
- SAST
- DAST
- Focused regression tests
Mappings
Related CVEs, CWEs, and ATT&CK context
Related CWEs
ATT&CK Relevance
ATT&CK relevance is shown only when reviewed or responsibly inferred.