DoS (Denial of Service) org.xerial.snappy:snappy-java Dependency in Bitbucket Data Center and Server

This High severity org.xerial.snappy:snappy-java Dependency vulnerability was introduced in versions 7.21.0, 8.9.0 and 8.13.0 of Bitbucket Data Center and Server.

This org.xerial.snappy:snappy-java Dependency vulnerability, with a CVSS Score of 7.5 and a CVSS Vector of CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H allows an unauthenticated attacker to expose assets in your environment susceptible to exploitation which has no impact to confidentiality, no impact to integrity, high impact to availability, and requires no user interaction.

Atlassian recommends that Bitbucket Data Center and Server customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions:

• Bitbucket Data Center and Server 7.21: Upgrade to a release greater than or equal to 7.21.21

• Bitbucket Data Center and Server 8.9: Upgrade to a release greater than or equal to 8.9.5

• Bitbucket Data Center and Server 8.13: Upgrade to a release greater than or equal to 8.13.1

See the release notes (https://confluence.atlassian.com/bitbucketserver/release-notes). You can download the latest version of Bitbucket Data Center and Server from the download center (https://www.atlassian.com/software/bitbucket/download-archives).

The National Vulnerability Database provides the following description for this vulnerability: 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.