CVE 2005-2471
pstopnm in netpbm does not properly use the "-dSAFER" option when calling Ghostscript to convert a PostScript file into a (1) PBM, (2) PGM, or (3) PNM file, which allows external user-assisted attackers to execute arbitrary commands.
See the 
CVE page on Mitre.org
for more details.
