CVE:CVE-2015-7977
CNNVD:CNNVD-201602-082
NTP（Network Time Protocol，网络时间协议）是一款通过网络同步计算机时钟的协议。
NTP 4.2.8p6之前的版本和4.3.90之前的4.3.x版本中的ntpd存在安全漏洞。远程攻击者可借助ntpdc reslist命令利用该漏洞造成拒绝服务（空指针逆向引用）。
solution:Upgrade ntp ntp to a higher version than 4.2.8,4.3.90,4.2.8,4.2.8:p1,4.2.8:p1-beta1,4.2.8:p1-beta2,4.2.8:p1-beta3,4.2.8:p1-beta4,4.2.8:p1-beta5,4.2.8:p1-rc1,4.2.8:p1-rc2,4.2.8:p2,4.2.8:p2-rc1,4.2.8:p2-rc2,4.2.8:p2-rc3,4.2.8:p3,4.2.8:p3-rc1,4.2.8:p3-rc2,4.2.8:p3-rc3,4.2.8:p4,4.2.8:p5,and avoid the version (,4.2.8],[4.3.0,4.3.90),4.2.8,4.2.8:p1,4.2.8:p1-beta1,4.2.8:p1-beta2,4.2.8:p1-beta3,4.2.8:p1-beta4,4.2.8:p1-beta5,4.2.8:p1-rc1,4.2.8:p1-rc2,4.2.8:p2,4.2.8:p2-rc1,4.2.8:p2-rc2,4.2.8:p2-rc3,4.2.8:p3,4.2.8:p3-rc1,4.2.8:p3-rc2,4.2.8:p3-rc3,4.2.8:p4,4.2.8:p5; Upgrade oracle linux to a higher version than 6,and avoid the version 6; Upgrade siemens tim_4r-ie_firmware to a higher version than *; Upgrade siemens tim_4r-ie_dnp3_firmware to a higher version than -; Upgrade netapp clustered_data_ontap to a higher version than -; Upgrade netapp oncommand_balance to a higher version than -; Upgrade freebsd freebsd to a higher version than 9.3,9.3:p1,9.3:p10,9.3:p12,9.3:p13,9.3:p16,9.3:p19,9.3:p2,9.3:p20,9.3:p21,9.3:p22,9.3:p23,9.3:p24,9.3:p25,9.3:p28,9.3:p3,9.3:p30,9.3:p31,9.3:p32,9.3:p33,9.3:p34,9.3:p5,9.3:p6,9.3:p7,9.3:p8,9.3:p9,10.1,10.1:p1,10.1:p10,10.1:p12,10.1:p15,10.1:p16,10.1:p17,10.1:p18,10.1:p19,10.1:p2,10.1:p22,10.1:p24,10.1:p25,10.1:p26,10.1:p27,10.1:p3,10.1:p4,10.1:p5,10.1:p6,10.1:p7,10.1:p8,10.1:p9,10.2,10.2:p1,10.2:p10,10.2:p2,10.2:p5,10.2:p7,10.2:p8,10.2:p9,and avoid the version 9.3,9.3:p1,9.3:p10,9.3:p12,9.3:p13,9.3:p16,9.3:p19,9.3:p2,9.3:p20,9.3:p21,9.3:p22,9.3:p23,9.3:p24,9.3:p25,9.3:p28,9.3:p3,9.3:p30,9.3:p31,9.3:p32,9.3:p33,9.3:p34,9.3:p5,9.3:p6,9.3:p7,9.3:p8,9.3:p9,10.1,10.1:p1,10.1:p10,10.1:p12,10.1:p15,10.1:p16,10.1:p17,10.1:p18,10.1:p19,10.1:p2,10.1:p22,10.1:p24,10.1:p25,10.1:p26,10.1:p27,10.1:p3,10.1:p4,10.1:p5,10.1:p6,10.1:p7,10.1:p8,10.1:p9,10.2,10.2:p1,10.2:p10,10.2:p2,10.2:p5,10.2:p7,10.2:p8,10.2:p9; Upgrade fedoraproject fedora to a higher version than 22,23,and avoid the version 22,23; Upgrade debian debian_linux to a higher version than 8.0,9.0,and avoid the version 8.0,9.0; Upgrade canonical ubuntu_linux to a higher version than 12.04,14.04,16.04,and avoid the version 12.04,14.04,16.04