JavaScript-based attacks taking advantage of an Adobe Reader and Acrobat vulnerability patched in 2010 are continuing in waves, Symantec researchers said this week. The security bug relates to an invalid TIFF value that corrupts the image file format's parser, senior software engineer Jason Zhang said in a blog post. Symantec said its technology has blocked more than 10,000 malicious PDF file attempts over the past two weeks, with the largest campaign coming on Feb. 16, two years to the date after the flaw was patched. Users are advised to update their Reader and Acrobat software.