The pmmallocarray2 function in lib/util/mallocvar.c in Netpbm through 10.81.03 allows remote attackers to cause a denial of service (heap-based buffer over-read) via a crafted image file, as demonstrated by pbmmask.
tiffttopnm in netpbm 10.47.63 does not properly use the libtiff TIFFRGBAImageGet function, which allows remote attackers to cause a denial of service (out-of-bounds read and write) via a crafted tiff image file, related to transposing width and height values.