CWE-242 Use of Inherently Dangerous Function

The product calls a function that can never be guaranteed to work safely, regardless of how it is used.

• Other: Varies by Context — The consequences vary depending on the behavior of the affected function. • Other: Modify Memory — Some functions can be subject to buffer overflows. For example, an attacker can easily send arbitrarily-sized input to gets() and overflow the destination buffer. In C++, an attacker can easily send arbitrarily-sized input to the >> operator and overflow the destination buffer.

• [Build and Compilation, Implementation] Identify a list of prohibited API functions and prohibit developers from using these functions, providing safer alternatives. In some cases, automatic code analysis tools or the compiler can be instructed to spot use of prohibited functions, such as the "banned.h" include file from Microsoft's SDL. [REF-554] [REF-1009] [REF-7] • [Testing] Use grep or static analysis tools to spot usage of dangerous functions.

• 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.)

• CVE-2007-4004: FTP client uses inherently insecure gets() function and is setuid root on some systems, allowing buffer overflow