A Denial of Service vulnerability exists in the Juniper Networks Junos OS JDHCPD daemon which allows an attacker to core the JDHCPD daemon by sending a crafted IPv6 packet to the system. This issue is limited to systems which receives IPv6 DHCP packets on a system configured for DHCP processing using the JDHCPD daemon. This issue does not affect IPv4 DHCP packet processing. Affected releases are Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S10 on EX Series; 12.3X48 versions prior to 12.3X48-D70 on SRX Series; 14.1X53 versions prior to 14.1X53-D47 on EX2200/VC EX3200 EX3300/VC EX4200 EX4300 EX4550/VC EX4600 EX6200 EX8200/VC (XRE) QFX3500 QFX3600 QFX5100; 14.1X53 versions prior to 14.1X53-D130 on QFabric; 15.1 versions prior to 15.1R4-S9 15.1R6-S6 15.1R7; 15.1X49 versions prior to 15.1X49-D140 on SRX Series; 15.1X53 versions prior to 15.1X53-D67 on QFX10000 Series; 15.1X53 versions prior to 15.1X53-D233 on QFX5110 QFX5200; 15.1X53 versions prior to 15.1X53-D471 on NFX 150 NFX 250; 16.1 versions prior to 16.1R3-S9 16.1R4-S8 16.1R5-S4 16.1R6-S3 16.1R7; 16.2 versions prior to 16.2R2-S5 16.2R3; 17.1 versions prior to 17.1R1-S7 17.1R2-S7 17.1R3; 17.2 versions prior to 17.2R1-S6 17.2R2-S4 17.2R3; 17.3 versions prior to 17.3R1-S4 17.3R2-S2 17.3R3; 17.4 versions prior to 17.4R1-S3 17.4R2.