Libcupsfilters: cups-filters: libcupsfilters: cups image filter process abort via malformed png

A flaw was found in libcupsfilters and cups-filters. The PNG image reading function creates a libpng reader without installing an error recovery handler, causing the CUPS image filter process to abort when processing a malformed PNG file. An unauthenticated attacker could exploit this by submitting a specially crafted PNG print job, leading to denial of service of the in-flight print job.