An integer overflow flaw was found in the way vim handled tree length values when reading an undo file. This bug could result in vim crashing when trying to process corrupted undo files. An integer overflow flaw was found in the way vim handled undo files. This bug could result in vim crashing when trying to process corrupted undo files.vim before patch 8.0.0322 does not properly validate values for tree length when handling a spell file, which may result in an integer overflow at a memory allocation site and a resultant buffer overflow