From Jeffrey Morlan:

pst_parse_block misreads Table Contexts (aka "type 2") with a
multi-block Row Matrix ("ind2"). Rows are never split between blocks -
every block except the last has padding at the end which should be
ignored. I've only seen this affect the recipients table, but
presumably it could affect attachments too. This was causing
out-of-bounds memory ranges to be returned from pst_getBlockOffset and
later access; patch fixes both the table reading issue and adds a
missing bounds check to pst_getBlockOffset (so as not to risk a
segfault if the PST is corrupted).