IPX is Vulnerable to Path Traversal via Prefix Matching Bypass

IPX is an image optimizer powered by sharp and svgo. In versions 1.3.1 and below, 2.0.0-0 through 2.1.0, and 3.0.0 through 3.1.0, the approach used to check whether a path is within allowed directories is vulnerable to path prefix bypass when the allowed directories do not end with a path separator. This occurs because the check relies on a raw string prefix comparison. This is fixed in versions 1.3.2, 2.1.1 and 3.1.1.