I think that such cables are coloured yellow (mine is).
Yellow plastic doth not a x-over cable make!
RJ45 Ethernet cables can be any colour under the sun.
The way to check is to look at the insulation on the individual wires where they are crimped in the transparent plastic terminating plugs at each end of the cable. If the colour sequence is identical at both ends, that's straight-through. If it isn't, then it's a x-over.
SD