CVE:CVE-2018-20481
CNNVD:CNNVD-201812-1145
Poppler是一个用于生成PDF的C++类库，该库是从Xpdf（PDF阅读器）继承而来。
Poppler 0.72.0版本中的XRef.cc文件的XRef::getEntry存在安全漏洞，该漏洞源于程序错误的处理了未分配的条目。远程攻击者可借助特制的PDF文档利用该漏洞造成拒绝服务（空指针逆向引用）。
solution:Upgrade freedesktop poppler to a higher version than 0.72.0,and avoid the version 0.72.0; Upgrade canonical ubuntu_linux to a higher version than 14.04,16.04,18.04,18.10,and avoid the version 14.04,16.04,18.04,18.10; Upgrade debian debian_linux to a higher version than 8.0,and avoid the version 8.0