CentOS 7.x pdftk
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<yambe:breadcrumb>CentOS_7.x_command_line_tools_and_utilities|CentOS 7.x command line tools and utilities</yambe:breadcrumb>
CentOS 7.x pdftk
You can also refer to older CentOS 6.x pdftk article.
On CentOS 7 you might have to install pdftk using:
yum -y install libstdc++.i686 yum -y install pdftk
as pdftk is using 32-bit version of libstdc++ library.