Since there are some sites using PDF, this alert came through very good source - Edupage newsletter. The virus alerts through this newsletter are extreme rare and posted only if there is concerns. NEW VIRUS SPREADS USING ACROBAT FILES Portable Document Format (PDF) files used in Adobe Acrobat are susceptible to an experimental virus, according to analysis by HispaSec Sistemas head Bernardo Quinteros and Privacy Foundation CTO Richard M. Smith. Quinteros and Smith say the virus, Outlook.pdf, embeds itself in PDF files via Outlook. Users who open the file with Acrobat are encouraged to click on an image of a peach, thus releasing the virus. The e-mail addresses in Outlook's Address Book and its folder are used to spread Outlook.pdf. "Since PDF files are considered safe by Internet Explorer, it means that Acrobat security holes are easy to exploit from Web pages and HTML e-mail messages," warned Smith. (InfoWorld.com, 8 August 2001)