Affected: Maven: org.xerial.snappy:snappy-java

## Summary Due to unchecked multiplications, an integer overflow may occur, causing a fatal error. ## Impact Denial of Service ## Description The function [shuffle(int[] input)](https://github.com/xerial/snappy-java/blob/05c39b2ca9b5b7b39611529cc302d3d796329611/src/main/java/org/xerial/snappy/BitShuffle.java#L107) in the file [BitShuffle.java](https://github.com/xerial/snappy-java/blob/master/src/main/java/org/xerial/snappy/BitShuffle.java) receives an array of integers and applies a bit shuffle on it. It does so by multiplying the length by 4 and passing it to the natively compiled shuffle function.

```java public static byte[] shuffle(int[] input) throws IOException { byte[] output = new byte[input.length * 4]; int numProcessed = impl.shuffle(input, 0, 4, input.length * 4, output, 0); assert(numProcessed == input.length * 4); return output; }

```

Since the length is not tested, the multiplication by four can cause an integer overflow and become a smaller value than the true size, or even zero or negative. In the case of a negative value, a “java.lang.NegativeArraySizeException” exception will raise, which can crash the program. In a case of a value that is zero or too small, the code that afterwards references the shuffled array will assume a bigger size of the array, which might cause exceptions such as “java.lang.ArrayIndexOutOfBoundsException”. The same issue exists also when using the “shuffle” functions that receive a double, flo…