Help in a panic, think someone's been tampering with my lock

[Curious1]

I returned home this afternoon to find my front door lock was full of gunk? Upon inspection it appears to smell like Vaseline with perhaps an ever so slightly blue hue off it. After inserting my key a couple of times it appears to be gone and was not hard or sticky like glue more lubricating.
I am now obviously concerned that someone has been tampering with my lock but wondered if anybody could give me an insight into what might have been put in it or the purpose.
Thank you in advance!

[mechanical_nightmare]

I'm not sure about the vaseline, but a blueish hue might mean that someone tried to impression the lock. Typically, a blue marker is run over the edge of a blank key to enhance marks made by the pins, so that the attacker may file the marks and eventually produce the key. Perhaps some of the more professional users on this site have a better idea?

[alockguru]

I doubt it would come from any kind of impressioning. Generally you avoid any kind of lubrication during that process.
Maybe it came from some type of insect. Maybe a snail or slug

[Squelchtone]

OP has not returned since signing up on Sept 8th. welcome to the internet...

[smokingman]

If the OP is lurking , or just for the sake of trying to solve a mystery,
locks are mostly brass, so maybe someone used China made brass cleaner
on the lock.
Some of these cleaners can cause a blueish residue to form on the metal
after use.
Maybe it was ghost pirates, darn those nosey kids.

[mechanical_nightmare]

I read the impressioning manual for amateur locksmiths and now understand why you wouldn't want lube while doing it. Thanks for letting me know.