CWE-1335βIncorrect Bitwise Shift of Integer
Metadata
Weakness Name
Incorrect Bitwise Shift of Integer
Description
An integer value is specified to be shifted by a negative amount or an amount greater than or equal to the number of bits contained in the value causing an unexpected or indeterminate result.
Specifying a value to be shifted by a negative amount is undefined in various languages. Various computer architectures implement this action in different ways. The compilers and interpreters when generating code to accomplish a shift generally do not do a check for this issue. Specifying an over-shift, a shift greater than or equal to the number of bits contained in a value to be shifted, produces a result which varies by architecture and compiler. In some languages, this action is specifically listed as producing an undefined result.