CWE-195 (有符号至无符号转换错误) — Vulnerability Class 22

CWE-195 represents a critical programming weakness involving the improper conversion of signed integers to unsigned types, often triggered by implicit casts that yield unexpected values when negative numbers are involved. Attackers typically exploit this vulnerability by supplying negative inputs to functions expecting unsigned parameters, causing the signed value to wrap around into a large positive integer. This manipulation can bypass security checks, trigger buffer overflows, or cause integer underflows, leading to memory corruption or denial of service. To mitigate this risk, developers must explicitly validate input ranges before conversion, ensuring values fall within the safe bounds of the target unsigned type. Utilizing static analysis tools to detect implicit casts and enforcing strict type checking during compilation further reduces the likelihood of such errors, thereby preserving data integrity and application stability against malicious exploitation.