Vulnerability details
Vulnerability
Data from Dependency-Track
Affected versions
Score
Description
### Impact
Several decompression paths in snappy-java allocate an output buffer sized by the uncompressed length declared in the first bytes of the compressed data, before decompressing or validating it. A few bytes of crafted input can therefore force an allocation of up to 2 GB, causing `OutOfMemoryError` (denial of service), or a `NegativeArraySizeException` for declared lengths of 2^31 or more.
Affected entry points include `Snappy.uncompress(byte[])`, `Snappy.uncompressString`, the `Snappy.uncompress*Array` methods, `SnappyInputStream`, and `SnappyFramedInputStream`. The `maxChunkSize` limit added for CVE-2023-43642 bounds only the compressed chunk length, so it does not prevent this.
### Patches
Fixed in 1.1.10.9 (#739). `Snappy.uncompressedLength()` now rejects negative declared lengths, and lengths larger than any valid Snappy stream of the given size can produce. The densest Snappy element expands 3 bytes to 64, so the limit is 64/3 of the compressed size. Allocations are therefore proportional to the input actually received.
### Workarounds
Before decompressing untrusted data, check that `Snappy.uncompressedLength(input)` is within an application-specific limit.