pnmtopng in netpbm before 10.25, when using the -trans option, uses uninitialized size and index variables when converting Portable Anymap (PNM) images to Portable Network Graphics (PNG), which might allow attackers to execute arbitrary code by modifying the stack.

Multiple vulnerabilities in NetPBM 9.20 and earlier, and possibly other versions, may allow remote attackers to cause a denial of service or execute arbitrary code via "maths overflow errors" such as (1) integer signedness errors or (2) integer overflows, which lead to buffer overflows.

Stack-based buffer overflow in converter/ppm/xpmtoppm.c in netpbm before 10.47.07 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via an XPM image file that contains a crafted header field associated with a large color index value.