Insurance Loophole found on BlackJack

[williamshennie9]

Hey admins/devs  

I have found a bug, which benefits the player 100% of the time. This definitely is costing stake a lot of money in lost revenue on blackjack.

I am posting this out of the goodness of my heart, and I don't want stake to suffer losses because of this. I am a firm supporter of stake and what they do (with the whole provably fair system), and I don't want anyone to take advantage of this.

When the dealer shows an ACE up card, the player can opt for insurance.

Here is the catch though: If the player clicks insurance, and the dealer has a blackjack, the Player will "break even" (like it should be).

BUT, if the dealer does not have a blackjack, NO MONEY IS DEDUCTED from the player's balance. The player does not pay for insurance.

In the first example Blackjack:747,102,276   -- I clicked the insurance button 5 times, and no money went off my account. I ENDED up betting 100 sats, I paid nothing for insurance, and I WON 200 sats.

[Please note, the bet says I lost 100 sats, but that is a visal bug, I took screen shots of before and after the game to prove that I got the full payout]

In the second example, Blackjack:747,207,484 -- I clicked insurance, BUT I DID NOT PAY FOR IT (my balance stayed the same - see pics). I should have lost an additional 50 sats for clicking "insurance", but I got the insurance for free.

Therefore, If I want insurance, and the dealer has a blackjack, I break even.

If I want insurance, and the dealer does not have a blackjack, the player does not pay for it [the insurance is free], and gets the full winnings if the player wins the bet.

@Dan @Edward Please test it for yourself on blackjack if you do not understand what I mean, but I have done this multiple times, just to make 100% sure that this is a real and very serious problem.

I love stake and hope this gets fixed soon before too many people figure this loophole out. If this doesn't make sense, please let me know, and I'll try to explain better

[testB]

As someone that doesn't normally play insurance, are you getting payout for that "free" insurance bet when Dealer does have BJ?

 

Hope the log counting wager/profit wrong when doubling/splitting get fixed soon, too.

 

Update:

Finally found one but wasn't keeping track of my balance: Blackjack:747,671,785

It could be just confusion about the rules, seems it affects the payout rather than it being a separate bet here. I did get confused about them rules (with those of other casinos) in that other thread I made myself.

[Dan]

Thanks for letting us know, will resolve soon. It's not a significant issue that we would consider it an exploit.

[williamshennie9]

That's quite interesting that it is not significant. If I owned a casino, and people got free insurance (especially if they bet larger amounts, eg 0.01 BTC), that is a "lost" revenue of 0.005 BTC per game played (where the dealer gets an Ace up card).

I would imagine that this would add up quickly, especially since there are many active players on Stake, who bet bet large amounts.

The thing for me is, It is impossible for the casino to make a profit if the dealer gets a blackjack because the player chooses insurance and breaks even (if the dealer ha a blackjack), or the dealer does not have a blackjack, in which case, insurance is free.

I would have also thought that this would be significant, since the dealer should have an Ace up card once every 13 games (or 7.7% of the time), and insurance is something that affects the house edge calculation, as it is usually profitable for the casino to offer insurance.

Just my thoughts on the matter, and why I think it is significant, but I could be wrong. I don't own a casino, so I do not know what is and is not significant 

[testB]

Currently, the insurance cost is being subtracted, but doesn't properly reflect in the balance without refreshing. It's a bit inconvenient, but they did fix the issue.

[williamshennie9]

@Dan @Bojana

Could someone please explain why I did not qualify for a reward for posting this?

According to the FAQ, non-visual bugs that warrant an update to the code, are eligible for a reward.

This bug, regardless of whether it was "significant" or not, this bug did make Stake lose money, and had I not pointed it out in this post, it could have gone undetected for much longer.

So I technically saved Stake some money  (by pointing this out)

I would appreciate a reply with regards to this, considering that the code has been updated, and that Stake has fixed the issue (which means that players can no longer take advantage of this).

[lolipant]

can someone explain how insurance works for me? i don't wanna bother a support  😢

am i suppose to break even or lose money when i win the insurance but lose base bet? (base bet 8552 is lose, while i won insurance with base 4276) what's the payout of the insurance?

12828 (got base insurance back, which is 2x payout) or 8552 (doesn't included base insurance)). i'm confuse because in verification page it show i lose -0.00004276 while in lastest blackjack game it show 0.00 (break even)

did i lose money here?

BLACKJACK: 856,168,932

placed by boobs on 23/09/2018

Wagered

0.00008552

Multiplier

0.666667x

Profit

0.00000000

[DanielRandomDud]

Lol this is really major issue i think for sure worth bug bounty,

[williamshennie9]

4 minutes ago, DanielRandomDud said:

Lol this is really major issue i think for sure worth bug bounty,

Thank you  I hope Dan agrees

I also saw that the insurance is messed up again, I made another post about that. I hope they fix it soon

8 minutes ago, lolipant said:

can someone explain how insurance works for me? i don't wanna bother a support  😢

am i suppose to break even or lose money when i win the insurance but lose base bet? (base bet 8552 is lose, while i won insurance with base 4276) what's the payout of the insurance?

12828 (got base insurance back, which is 2x payout) or 8552 (doesn't included base insurance)). i'm confuse because in verification page it show i lose -0.00004276 while in lastest blackjack game it show 0.00 (break even)

did i lose money here?

I've reported this as well, I think after they corrected the last problem, it bought about a whole new problem.

And the thing is, I love blackjack, and I play it all the time, so I am quickly aware of these issues when they happen

I will keep everyone informed with regards to when they fix these issues 

[DanielRandomDud]

2 minutes ago, williamshennie9 said:

Thank you  I hope Dan agrees

I also saw that the insurance is messed up again, I made another post about that. I hope they fix it soon

I've reported this as well, I think after they corrected the last problem, it bought about a whole new problem.

And the thing is, I love blackjack, and I play it all the time, so I am quickly aware of these issues when they happen

I will keep everyone informed with regards to when they fix these issues 

2 days ago there was bug that totally stucked you if you havent balance big enough to cover insurance

[williamshennie9]

1 minute ago, DanielRandomDud said:

2 days ago there was bug that totally stucked you if you havent balance big enough to cover insurance

Yeah, I've noticed the insurance bug for the past few days now. I just like to run my own tests to make 100% sure it is a real bug before I bother the developers with it.

You can find my official post under Questions, Bugs, Issues & Complaints section of the forum

[lolipant]

on top of that, there's a bug when you can't double when you get 12+ hand as well. not sure it is a bug or they change the rule (already reported on live support twice tho)

[DanielRandomDud]

1 minute ago, williamshennie9 said:

Yeah, I've noticed the insurance bug for the past few days now. I just like to run my own tests to make 100% sure it is a real bug before I bother the developers with it.

You can find my official post under Questions, Bugs, Issues & Complaints section of the forum

from my own experience (3 years of bug hunting)

sites are way more opened to giving you massive rewards if you also provide them with possible solutions.

in code or at least idea on paper

1 minute ago, lolipant said:

on top of that, there's a bug when you can't double when you get 12+ hand as well. not sure it is a bug or they change the rule (already reported on live support twice tho)

i know in some casinos you can double down at anytime. Not sure why you cant do it there

[williamshennie9]

1 minute ago, lolipant said:

on top of that, there's a bug when you can't double when you get 12+ hand as well. not sure it is a bug or they change the rule (already reported on live support twice tho)

I don't think that is a bug, most casinos don't let you double on hands, expect if your hand is 9,10,11

It is the same with doubling on a split hand  Some casinos just don't allow it.

2 minutes ago, DanielRandomDud said:

from my own experience (3 years of bug hunting)

sites are way more opened to giving you massive rewards if you also provide them with possible solutions.

in code or at least idea on paper

Lol, I don't know how I would give coding suggestions becuase I don't think Stake makes the source code available for their games (I could be wrong though).

I think if they made the code publicly available, everyone would try make an online casino to rake in profits

[lolipant]

3 minutes ago, DanielRandomDud said:

i know in some casinos you can double down at anytime. Not sure why you cant do it there

you're suppose to able to double down any hand (i can confirm it is that way before the recent maintainance) 

it's also confirmed here: 

 

[1n0n7y]

Never take insurance. Unless it is for free, of course 👻

[lolipant]

another one: can't re-hit after split ace (you can see on above link it didn't play by this rule)

BLACKJACK: 856,626,922

placed by boobs on 23/09/2018

Wagered

0.00000000

Multiplier

2x

Profit

0.00000000

edit: in my past bet pre-update i can re-hit after split ace just fine Blackjack:721,715,460

[williamshennie9]

4 hours ago, lolipant said:

you're suppose to able to double down any hand (i can confirm it is that way before the recent maintainance) 

it's also confirmed here: 

 

Those rules were made over a year ago - perhaps they have changed?

Let's just wait and see what Dan has to say

[rczII]

4 hours ago, 1n0n7y said:

Never take insurance. Unless it is for free, of course 👻

never surrender never insurance :))))

[testB]

Not that it's worth anything, but I can confirm the issue did exist. However, it's possible they were already made aware of it by someone else, or they found it themselves. 

On the other hand, it might be time to archive this thread, since the current version's issues are a bit different from the ones discussed here. Just so things don't get mixed up.

@rczll Agreed