In Libarchive 3.4.0, archive_wstring_append_from_mbs in archive_string.c has an out-of-bounds read because of an incorrect mbrtowc or mbtowc call. For example, bsdtar crashes via a crafted archive.

archive_read_support_format_rar5.c in libarchive before 3.4.2 attempts to unpack a RAR5 file with an invalid or corrupted header (such as a header size of zero), leading to a SIGSEGV or possibly unspecified other impact.