CWE-453: Insecure Default Variable Initialization
The product, by default, initializes an internal variable with an insecure or less secure value than is possible.
How it's found
Insecure Default Variable Initialization is a specific, narrowly defined instance of a broader pattern. Testers confirm it with targeted code review and a proof-of-concept input that exercises the exact code path this weakness describes.
Vulnerable vs. safe
// $user and $pass automatically set from POST request
...$authorized = true;
generatePage();if (login_user($user,$pass)) {}if ($authorized) {}$authorized = true;...$user = $_POST['user'];$pass = $_POST['pass'];$authorized = false;if (login_user($user,$pass)) {}Consequences
- Modify Application Data: An attacker could gain access to and modify sensitive data or system information.
Mitigations
- System Configuration: Disable or change default settings when they can be used to abuse the system. Since those default settings are shipped with the product they are likely to be known by a potential attacker who is familiar with the product. For instance, default credentials should be changed or the associated accounts should be disabled.
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-453?
The product, by default, initializes an internal variable with an insecure or less secure value than is possible.
How do you find Insecure Default Variable Initialization?
Insecure Default Variable Initialization is a specific, narrowly defined instance of a broader pattern. Testers confirm it with targeted code review and a proof-of-concept input that exercises the exact code path this weakness describes.
What is the impact of CWE-453?
Modify Application Data: An attacker could gain access to and modify sensitive data or system information.
Does TurboPentest test for Insecure Default Variable Initialization?
This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.
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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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