Multiplayer game files hacked?

[TonyAfan]

Hi
A couple of weeks ago I accepted a challenge posted by a player username aiai. The scenario was a paired game of the Italy scenario. Both games were hard fought but as the Allies I had cleared Sicily and taken Reggio di Calabria. I had managed to insert a strong defensive force below Catanzaro blocking an attack on Reggio di Calabria. He had a limited attacking force left; his main attacking threat was a panther plus some infantry and AA guns and an Italian Mobile artillery unit. With just a few turns left I was quietly confident of victory.

I then received his axis turn 19. I was stunned most of my troops were gone Including my navy, and the forces I still had on Sicily had disappeared, the only troops left were a depleted M12 Mobile Artillery unit and a landing craft with an embarked AT gun. The replay of his turn showed him taking Reggio di Calabria with a couple of Calvary units and a mountain infantry unit then the game ended with an axis win. I saved the replay of the scenario, all the replay showed was his final turn.
My prestige points had changed also the name of the scenario had been changed to Operation Unthinkable even though the scenario was still Italy..
I thought that it was not possible to change multiplayer game files.
So it looks like my opponent can change the multiplayer files without corrupting the game.
Has anyone who plays multiplayer come across anything like this before?
Screenshots are the end position after my turn 19 and the position after their turn 19.

[TonyAfan]

Hi
He did the same in the paired game. As the axis I was fighting to take control back of Reggio di Calabria .I thought it was unlikely I would hold the town even if I took it on my final turn. As it was I didn't have the chance again he removed all my units from the map flooded the map with paratroopers and renamed the scenario.

[bondjamesbond]

Hi !
I don’t get why you’re messing about with this con artist or hacker – or do you enjoy masochism, or is this some sort of experiment to see if you can cheat in multiplayer?

[TonyAfan]

Hi
I play multiplayer games often and this is the first time I have experienced this. I didn't realise it was to possible to change multiplayer game files like this. This was the first time to my knowledge I had played this person so I was not expecting for the game to be hacked. I was wondering if other players had the same experience as me. If I post this then other players might avoid the waste of time it is to play this person in multiplayer.

[Tobi72]

Hi
I play multiplayer games often and this is the first time I have experienced this. I didn't realise it was to possible to change multiplayer game files like this. This was the first time to my knowledge I had played this person so I was not expecting for the game to be hacked. I was wondering if other players had the same experience as me. If I post this then other players might avoid the waste of time it is to play this person in multiplayer.

Hi Tony,
First of all, I am not AIAI, and I don't play multiplayer games. But since I found this topic interesting, I asked my AI about it.

Its answer was:

“Yes, in principle AI could help someone analyse and manipulate multiplayer save or turn files, especially if important game data is stored locally and is not sufficiently validated by the server. AI does not magically ‘hack’ the game by itself, but it can make reverse-engineering file formats, identifying editable values and potentially modifying those values considerably easier.

AI is also capable of analysing Panzer Corps replay files. I have already tested this myself: Sol was able to read a .pzrpl replay file and reconstruct actions such as unit placement, movement, attacks and turn changes from the data.

If the multiplayer system accepts modified game or turn files without sufficient verification, manipulation like the behaviour you described could therefore theoretically be possible.”

Of course, without examining the actual multiplayer files involved and how the server validates them, this does not prove that this is what happened in your particular game.

But if someone really did use such a method to gain an unfair advantage in multiplayer, that would be a pretty nasty thing to do. After all, the other player is investing time and effort into the match and expects a fair game.

[TonyAfan]

Hi Tobi

I usually record the replay of my opponents turn so I can replay it in case I missed anything. So I can send those files if you wish to look at them. Also I saved the replays of the scenarios. However the replays only show aiai's last turn, none of the previous turns.
In both cases the name of the scenario has been changed from Italy to operation unthinkable even though the scenario map is still Italy. Username aiai may be a joke and they may not be using an AI to do what they are doing.
I do not know where the multiplayer game files are stored before uploading and downloading from the multiplayer server.
It will be interesting to see what type of campaigns your work with Sol will produce.

Best Wishes

TonyAfan

[Tobi72]

Hi Tobi

I usually record the replay of my opponents turn so I can replay it in case I missed anything. So I can send those files if you wish to look at them. Also I saved the replays of the scenarios. However the replays only show aiai's last turn, none of the previous turns.
In both cases the name of the scenario has been changed from Italy to operation unthinkable even though the scenario map is still Italy. Username aiai may be a joke and they may not be using an AI to do what they are doing.
I do not know where the multiplayer game files are stored before uploading and downloading from the multiplayer server.
It will be interesting to see what type of campaigns your work with Sol will produce.

Best Wishes

TonyAfan

Hi Tony,
Yes, if you are willing to send me the replay files, I would be interested in having Sol take a look at them.

Especially useful would be the replay from shortly before the strange final turn and the replay showing the final turn itself. Sol may be able to compare the files and see whether there are unusual changes in the stored game data, for example involving units, prestige, scenario information or the changed scenario name.

I cannot promise that we will be able to determine exactly what happened, because I do not yet know how the Panzer Corps multiplayer files are structured or how much information is actually stored in the replay files. But it would certainly be interesting to analyse them and see what can be found.

And I agree with you about the username “aiai” — that may simply be a joke and does not necessarily mean that AI was involved.

Best wishes,
Tobi

[Tobi72]

I carried out two controlled experiments with Sol using one of my own Panzer Corps save files.

First, Sol externally changed only the scenario name inside a copy of the .pzsav file. The modified save still loaded normally in Panzer Corps.

We then carried out a second, more important test. Sol identified the stored prestige value in my save and changed it from its original value to 5000, without changing the file size or otherwise altering the save structure.

I loaded the modified save in Panzer Corps and the game accepted it and showed the changed prestige value correctly.

So we have now demonstrated that Panzer Corps save files can not only be externally modified without being rejected by the game, but that actual gameplay values such as prestige can also be changed successfully.

This does not by itself prove who altered Tony’s multiplayer games or exactly how it was done, but it clearly shows that the underlying save data is technically modifiable and that such changes can remain valid and loadable in the game.

[bondjamesbond]

Now it’s clear why they don’t hold World Championships any more ) ! I wonder if they could pull something like that off in the second part as well !

[TonyAfan]

Hi Bond

They did