Summary
Due to unchecked multiplications, an integer overflow may occur, causing a fatal error.
Impact
Denial of Service
Description
The function shuffle(int[] input) in the file 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.
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, float, long and short, each using a different multiplier that may cause the same issue.
Steps To Reproduce
Compile and run the following code:
package org.example;
import org.xerial.snappy.BitShuffle;
import java.io.*;
public class Main {
public static void main(String[] args) throws IOException {
int[] original = new int[0x40000000];
byte[] shuffled = BitShuffle.shuffle(original);
System.out.println(shuffled[0]);
}
}
The program will crash, showing the following error (or similar):
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 0 out of bounds for length 0
at org.example.Main.main(Main.java:12)
Process finished with exit code 1
Alternatively - compile and run the following code:
package org.example;
import org.xerial.snappy.BitShuffle;
import java.io.*;
public class Main {
public static void main(String[] args) throws IOException {
int[] original = new int[0x20000000];
byte[] shuffled = BitShuffle.shuffle(original);
}
}
The program will crash with the following error (or similar):
Exception in thread "main" java.lang.NegativeArraySizeException: -2147483648
at org.xerial.snappy.BitShuffle.shuffle(BitShuffle.java:108)
at org.example.Main.main(Main.java:11)
Credit
The vulnerability was discovered by Ori Hollander of the JFrog Security Research Team
Summary
Due to unchecked multiplications, an integer overflow may occur, causing a fatal error.
Impact
Denial of Service
Description
The function shuffle(int[] input) in the file 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.
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, float, long and short, each using a different multiplier that may cause the same issue.
Steps To Reproduce
Compile and run the following code:
The program will crash, showing the following error (or similar):
Alternatively - compile and run the following code:
The program will crash with the following error (or similar):
Credit
The vulnerability was discovered by Ori Hollander of the JFrog Security Research Team