Race condition in the Op command in Juniper Junos OS before 12.1X44-D55, 12.1X46 before 12.1X46-D40, 12.1X47 before 12.1X47-D25, 12.3 before 12.3R11, 12.3X48 before 12.3X48-D20, 12.3X50 before 12.3X50-D50, 13.2 before 13.2R8, 13.2X51 before 13.2X51-D39, 13.2X52 before 13.2X52-D30, 13.3 before 13.3R7, 14.1 before 14.1R6, 14.1X53 before 14.1X53-D30, 14.2 before 14.2R4, 15.1 before 15.1F2 or 15.1R2, 15.1X49 before 15.1X49-D10 or 15.1X49-D20, and 16.1 before 16.1R1 allows remote authenticated users to gain privileges via the URL option.