snappy-java integer overflow in shuffle leads to DoS
org.xerial.snappy:snappy-java
(,1.1.10.1)
snappy-java is a fast compressor/decompressor for Java. Due to unchecked multiplications, an integer overflow may occur in versions prior to 1.1.10.1, causing a fatal error.
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.
Version 1.1.10.1 contains a patch for this vulnerability.
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]);
}
}
No mitigations are supplied for this issue
https://github.com/xerial/snappy-java/blob/master/src/main/java/org/xerial/snappy/BitShuffle.java
https://github.com/xerial/snappy-java/commit/820e2e074c58748b41dbd547f4edba9e108ad905
https://github.com/xerial/snappy-java/security/advisories/GHSA-pqr6-cmr2-h8hf