Weakness · Medium
CWE-495: Private Data Structure Returned From A Public Method
What it is
The product has a method that is declared public, but returns a reference to a private data structure, which could then be modified in unexpected ways.
- Severity (our rating)
- Medium
- Likelihood of exploit
- Not rated by MITRE
- Introduced during
- Implementation
- Exploited in the wild
- No CVE in CISA's catalog
What an attacker can do
- Modify Application Data (Integrity)
How to prevent it
Implementation
- Declare the method private.
- Clone the member data and keep an unmodified version of the data private to the object.
- Use public setter methods that govern how a private member can be modified.
How to find it
- 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.)
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Start freeSource: MITRE Common Weakness Enumeration, CWE version 4.19.1. CWE is a trademark of The MITRE Corporation.