CVE-2026-116590: snappy-java: JVM crash from unchecked ranges in Snappy.arrayCopy and SnappyOutputStream.rawWrite

Vulnerability summary

CVE-2026-116590 is a medium (CVSS 5.9) Improper Validation of Array Index vulnerability in xerial snappy-java. EPSS estimates a 0.41% chance of exploitation in the next 30 days, higher than 35% of scored vulnerabilities.

Timeline

1. 26-10-2026
   PublishedVulnerability first disclosed.
2. 30-10-2026
   Last modifiedVulnerability information updated.

Description

snappy-java is a Java port of the snappy, a fast C++ compresser/decompresser developed by Google. Prior to 1.1.10.9, Snappy.arrayCopy(Object src, int offset, int byteLength, Object dest, int destOffset) passes caller-supplied ranges to native memcpy without validating either array, allowing negative or oversized byteLength and offset values to read or write outside array bounds and crash the JVM. SnappyOutputStream.rawWrite and SnappyInputStream.rawRead, including their typed-array write and read methods, pass caller-controlled ranges through this primitive, and typed-array byte-size calculations can overflow int. This issue is fixed in version 1.1.10.9.

• CWE-129Improper Validation of Array IndexThe product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array.
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.