A Denial of Service vulnerability in J-Web service may allow a remote unauthenticated user to cause Denial of Service which may prevent other users to authenticate or to perform J-Web operations. Affected releases are Juniper Networks Junos OS: 12.1X46 versions prior to 12.1X46-D77 on SRX Series; 12.3 versions prior to 12.3R12-S10; 12.3X48 versions prior to 12.3X48-D60 on SRX Series; 15.1 versions prior to 15.1R7; 15.1F6; 15.1X49 versions prior to 15.1X49-D120 on SRX Series; 15.1X53 versions prior to 15.1X53-D59 on EX2300/EX3400 Series; 15.1X53 versions prior to 15.1X53-D67 on QFX10K Series; 15.1X53 versions prior to 15.1X53-D234 on QFX5200/QFX5110 Series; 15.1X53 versions prior to 15.1X53-D470, 15.1X53-D495 on NFX Series; 16.1 versions prior to 16.1R6; 16.2 versions prior to 16.2R2-S6, 16.2R3; 17.1 versions prior to 17.1R2-S6, 17.1R3; 17.2 versions prior to 17.2R3; 17.3 versions prior to 17.3R2. No other Juniper Networks products or platforms are affected by this issue.