Portable Document format (PDF) files have increasingly been used as a means to deliver spammers' advertisements, but only rarely has the file format been used as an attack vector.

PD F文件已被越来越多地用来作为一种手段来运送垃圾邮件广告，但只有少数的文件格式被用来作为一个攻击向量。

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RightDoc is now delivering RightDoc 2.0, a business document writer that uses XML and Cascading Style Sheets (CSS) as its file formats, and can output HTML, Portable Document Format, and PostScript formats.

CNN: XML comes of age at Internet World