Incorrect Behavior Order: Early Validation
The product validates input before applying protection mechanisms that modify the input, which could allow an attacker to bypass the validation via dangerous inputs that only arise after the modification.
Product needs to validate data at the proper time, after data has been canonicalized and cleansed. Early validation is susceptible to various manipulations that result in dangerous inputs that are produced by canonicalization and cleansing.
Impact: Bypass Protection MechanismExecute Unauthorized Code or Commands
An attacker could include dangerous input that bypasses validation protection mechanisms which can be used to launch various attacks including injection attacks, execute arbitrary code or cause other unintended behavior.
Strategy: Input Validation
ID : DX-35
The following code attempts to validate a given input path by checking it against an allowlist and then return the canonical path. In this specific case, the path is considered valid if it starts with the string "/safe_dir/".Code Example:
javaCode Example:
javaID : DX-36
This script creates a subdirectory within a user directory and sets the user as the owner.Code Example:
php//filter out '' because other scripts identify user directories by this prefix*
$dirName = str_replace('','',$dirName);
$newDir = $userDir . $dirName;
mkdir($newDir, 0700);
chown($newDir,$userName);}
- PLOVER