CWE-499: Serializable Class Containing Sensitive Data | Glexia
CWE-499 (Serializable Class Containing Sensitive Data) weakness overview with consequences, detection methods, mitigations, related CVEs and MITRE ATT&CK context.
Glexia's Take · Automated analysis
CWE-499: Serializable Class Containing Sensitive Data
Serializable Class Containing Sensitive Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Confidentiality: Read Application Data: an attacker can write out the class to a byte stream, then extract the important data from it.
Developer Pattern
CWE-499 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-499, 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-499: Serializable Class Containing Sensitive Data
The code contains a class with sensitive data, but the class does not explicitly deny serialization. The data can be accessed by serializing the class through another class.
Serializable classes are effectively open classes since data cannot be hidden in them. Classes that do not explicitly deny serialization can be serialized by any other class, which can then in turn use the data stored inside it.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- This code creates a new record for a medical patient: This object does not explicitly deny serialization, allowing an attacker to serialize an instance of this object and gain a patient's name and Social Security number even though those fields are private.
Remediation
- Implementation: In Java, explicitly define final writeObject() to prevent serialization. This is the recommended solution. Define the writeObject() function to throw an exception explicitly denying serialization.
- Implementation: Make sure to prevent serialization of your objects.
Detection
- Automated Static Analysis: Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
Mappings
Related CVEs, CWEs, and ATT&CK context
Related CWEs
ATT&CK Relevance
ATT&CK relevance is shown only when reviewed or responsibly inferred.