CWE-766: Critical Data Element Declared Public
The product declares a critical variable, field, or member to be public when intended security policy requires it to be private.
How it's found
Critical Data Element Declared Public is typically found by tracing untrusted input from where it enters the system to the point where it is used without the check or neutralization this weakness describes, combining manual code review with dynamic testing.
This issue makes it more difficult to maintain the product, which indirectly affects security by making it more difficult or time-consuming to find and/or fix vulnerabilities. It also might make it easier to introduce vulnerabilities.
Vulnerable vs. safe
public: char* password;private: char* password;Consequences
- Read Application Data, Modify Application Data: Making a critical variable public allows anyone with access to the object in which the variable is contained to alter or read the value.
- Reduce Maintainability
Mitigations
- Implementation: Data should be private, static, and final whenever possible. This will assure that your code is protected by instantiating early, preventing access, and preventing tampering.
Where this fits in a TurboPentest engagement
This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.
Frequently asked questions
What is CWE-766?
The product declares a critical variable, field, or member to be public when intended security policy requires it to be private.
How do you find Critical Data Element Declared Public?
Critical Data Element Declared Public is typically found by tracing untrusted input from where it enters the system to the point where it is used without the check or neutralization this weakness describes, combining manual code review with dynamic testing.
What is the impact of CWE-766?
Read Application Data, Modify Application Data: Making a critical variable public allows anyone with access to the object in which the variable is contained to alter or read the value. Reduce Maintainability
Does TurboPentest test for Critical Data Element Declared Public?
This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.
Related CWEs
Written and reviewed by
Michel Chamberland - Founder & CEO, IntegSec
CISSP, OSCP, OSCE, CEH, GIAC, CCSK · 20+ years in offensive security
Michel has spent 20+ years on offensive security teams including IBM X-Force Red and Trustwave SpiderLabs, leading penetration tests, red team engagements, and breach response for Fortune 500 customers. He is the founder of IntegSec and the architect of TurboPentest.
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