someone fucked up and lost ALOT of money

[genjix]

thanks to phantomcircuit for asking me to investigate:

Code:

 depth  | index_in_block |   encode   |    value     |                             tx_hash                              |    when_created     
--------+----------------+------------+--------------+------------------------------------------------------------------+---------------------
 150951 |             23 | 76a90088ac |  24.31000000 | 111291fcf8ab84803d42ec59cb4eaceadd661185242a1e8f4b7e49b79ecbe5f3 | 2011-10-28 21:11:28
 150951 |             22 | 76a90088ac | 100.00000000 | 81f591582b436c5b129f347fe7e681afd6811417973c4a4f83b18e92a9d130fd | 2011-10-28 21:11:28
 150951 |             21 | 76a90088ac |  37.00000000 | ddddf9f04b4c1d4e1185cacf5cf302f3d11dee5d74f71721d741fbb507062e9e | 2011-10-28 21:11:28
 150951 |             20 | 76a90088ac |  98.48055000 | 305fbc2ec7f7f2bc5a21d2dfb01a5fc52ab5d064a7278e2ecbab0d2a27b8c392 | 2011-10-28 21:11:28
 150951 |             19 | 76a90088ac |  39.81000000 | f0137a6b31947cf7ab367ae23942a263272c41f36252fcd3460ee8b6e94a84c1 | 2011-10-28 21:11:28
 150951 |             18 | 76a90088ac |  65.00000000 | 633acf266c913523ab5ed9fcc4632bae18d2a7efc1744fd43dd669e5f2869ce5 | 2011-10-28 21:11:28
 150951 |             17 | 76a90088ac | 100.00000000 | 5bd88ab32b50e4a691dcfd1fff9396f512e003d7275bb5c1b816ab071beca5ba | 2011-10-28 21:11:28
 150951 |             16 | 76a90088ac |  21.00000000 | 64c01fedd5cf6d306ca18d85e842f068e19488126c411741e089be8f4052df09 | 2011-10-28 21:11:28
 150951 |             15 | 76a90088ac |  35.78400000 | 3be0ac3dc1c3b7fa7fbe34f4678037ed733a14e801abe6d3da42bc643a651401 | 2011-10-28 21:11:28
 150951 |             14 | 76a90088ac | 100.00000000 | 9edab6e7fadf1d6006315ff9394c08a7bf42e19cf61502200a1f73994f8da94b | 2011-10-28 21:11:28
 150951 |             13 | 76a90088ac | 100.00000000 | 835d4dcc52e160c23173658de0b747082f1937d1184e8e1838e9394bc62c0392 | 2011-10-28 21:11:28
 150951 |             12 | 76a90088ac | 143.62000000 | aebe39a99114f1b46fc5a67289545e54cbfec92d08fc8ffc92dc9df4a15ea05a | 2011-10-28 21:11:28
 150951 |             11 | 76a90088ac | 367.75849319 | aa62bdd690de061a6fbbd88420f7a7aa574ba86da4fe82edc27e2263f8743988 | 2011-10-28 21:11:28
 150951 |             10 | 76a90088ac | 100.00000000 | 6a86e6a5e8d5f9e9492114dafe5056c5618222f5042408ad867d3c1888855a31 | 2011-10-28 21:11:28
 150951 |              9 | 76a90088ac |  35.78000000 | 7ad47a19b201ce052f98161de1b1457bacaca2e698f542e196d4c7f8f45899ab | 2011-10-28 21:11:28
 150951 |              8 | 76a90088ac | 100.00000000 | 0ca7f7299dc8d87c26c82badf9a303049098af050698c694fbec35c4b08fc3df | 2011-10-28 21:11:28
 150951 |              7 | 76a90088ac | 100.00000000 | 3ab5f53978850413a273920bfc86f4278d9c418272accddade736990d60bdd53 | 2011-10-28 21:11:28
 150951 |              6 | 76a90088ac | 497.00000000 | 03acfae47d1e0b7674f1193237099d1553d3d8a93ecc85c18c4bec37544fe386 | 2011-10-28 21:11:28
 150951 |              5 | 76a90088ac | 100.00000000 | 15ad0894ab42a46eb04108fb8bd66786566a74356d2103f077710733e0516c3a | 2011-10-28 21:11:28
 150951 |              4 | 76a90088ac | 200.00000000 | 2d00ef4895f20904d7d4c0bada17a8e9d47d6c049cd2e5002f8914bfa7f1d27b | 2011-10-28 21:11:28
 150951 |              3 | 76a90088ac |  98.00000000 | 6d39eeb2ae7f9d42b0569cf1009de4c9f031450873bf2ec84ce795837482e7a6 | 2011-10-28 21:11:28
 150951 |              2 | 76a90088ac | 100.00000000 | 07d33c8c74e945c50e45d3eaf4add7553534154503a478cf6d48e1c617b3f9f3 | 2011-10-28 21:11:28
 150951 |              1 | 76a90088ac |  45.82000000 | 6d5088c138e2fbf4ea7a8c2cb1b57a76c4b0a5fab5f4c188696aad807a5ba6d8 | 2011-10-28 21:11:28

2609.36304319 BTC of irretrievable money.

EDIT: explanation,

The script looks like: 76a90088ac

That's the standard transaction (tx for short) which is:

dup (0x76), hash160 (0xa9), 0x14 (push 20 bytes to the stack), .... (next 20 bytes of hash of public key), equalverify (0x88), checksig (0xac)

Only in this case the 0x14 has been replaced by 00, which in scripting language means push 0 bytes.

It's a tx which has been sent to nothing. Obviously someone was hacking at bitcoin or making a custom version and messed up- although I have no idea what it was doing with so much money.

[I.Goldstein]

Well, that's a price increase.

[MoonShadow]

And why is it unaccessible?

[worldinacoin]

I don't understand that list, can anyone kindly elaborate.  Deeply appreciated.

[chieffery]

I don't understand that list, can anyone kindly elaborate.  Deeply appreciated.

+1, a layman's would be nice.

[BTCurious]

As far as I understand it, someone sent money to an "address" that wasn't properly formatted. As such, the money is sent, but never arrives anywhere. Most likely this was done by someone with a non-standard client, because the standard client can't do this. So it's either someone messing around with modifying the standard client code, or someone with custom code altogether (think exchanges etc).

[randomguy7]

What, the network (the miners) accepts transactions with malformed destination addresses?

[tvbcof]

As far as I understand it, someone sent money to an "address" that wasn't properly formatted. As such, the money is sent, but never arrives anywhere. Most likely this was done by someone with a non-standard client, because the standard client can't do this. So it's either someone messing around with modifying the standard client code, or someone with custom code altogether (think exchanges etc).

There has been some recent whining about people not recieving the BTC from Mt Gox.  Hmmmm.

[BTCurious]

What, the network (the miners) accepts transactions with malformed destination addresses?

It shouldn't, but it did. There's currently an investigation at the miner in question how this happened.

[theymos]

http://blockexplorer.com/tx/5bd88ab32b50e4a691dcfd1fff9396f512e003d7275bb5c1b816ab071beca5ba#o1

I think it would be redeemable if you had 1111111111111111111114oLvT2.

[dunand]

It means that I'm approximately 0.00035% richer. Woo-ooh!

Sorry to hear that anyhow.

[genjix]

The script looks like: 76a90088ac

That's the standard transaction (tx for short) which is:

dup (0x76), hash160 (0xa9), 0x14 (push 20 bytes to the stack), .... (next 20 bytes of hash of public key), equalverify (0x88), checksig (0xac)

Only in this case the 0x14 has been replaced by 00, which in scripting language means push 0 bytes.

It's a tx which has been sent to nothing. Obviously someone was hacking at bitcoin or making a custom version and messed up- although I have no idea what it was doing with so much money.

[BTCurious]

It seems that coins were sent to the address "0", which is obviously not a valid address. This is impossible with the standard client, and as such was done by someone running custom code.
About the network accepting it, I'll quote a bit of IRC conversation:

[03:01] <Glyph-Minus-229> the protocol doesn't prevent sending to invalid addreses?
[03:02] <gmaxwell> No, the protocol makes MANY things possible.
[03:02] <gmaxwell> The transactions are little programs that govern their redemption.
[03:03] <gmaxwell> There is probably no polynomial time that can identify all unspendable transactions.

So basically, it's not really possible to check for all things that go wrong. The bitcoin protocol supports a lot more than just sending coins from A to B, even though that's mainly what you see in the normal client nowadays. The miners need to accept "unusual transactions" though, as long as they adhere to the bitcoin protocol.

That's as far as I understand it. Is that layman-approved?

[theymos]

@theymos, nope. It has no destination pubkey.

Ah, hash160 will always produce 20 bytes, and with equalverify leading zeroes matter. So it can't be spent.

[genjix]

Ah, hash160 will always produce 20 bytes, and with equalverify leading zeroes matter. So it can't be spent.

Yeah I realised that once I saw that 0x00 is OP_0 rather than push 0 bytes.

EDIT: on closer inspection, actually OP_0 is defined but not ever used. The normal behaviour of the client is to push 0 bytes, so there can't be any destination address.

[theymos]

@theymos, how do you get that number? I get: 1FYMZEHnszCHKTBdFZ2DLrUuk3dGwYKQxh

This is an address transaction, so assuming (incorrectly) that we're comparing numbers instead of bytes, the all-zero hash160 with the address I posted would work.

[chieffery]

It seems that coins were sent to the address "0", which is obviously not a valid address. This is impossible with the standard client, and as such was done by someone running custom code.
About the network accepting it, I'll quote a bit of IRC conversation:

[03:01] <Glyph-Minus-229> the protocol doesn't prevent sending to invalid addreses?
[03:02] <gmaxwell> No, the protocol makes MANY things possible.
[03:02] <gmaxwell> The transactions are little programs that govern their redemption.
[03:03] <gmaxwell> There is probably no polynomial time that can identify all unspendable transactions.

So basically, it's not really possible to check for all things that go wrong. The bitcoin protocol supports a lot more than just sending coins from A to B, even though that's mainly what you see in the normal client nowadays. The miners need to accept "unusual transactions" though, as long as they adhere to the bitcoin protocol.

That's as far as I understand it. Is that layman-approved?

+rep, appreciate the info, though now im left wondering...

[BTCurious]

Maybe this helps.
It seems MtGox made a mistake somewhere.

<MagicalTux> that's a problem, but not the worst problem we ever faced
<MagicalTux> all the broken withdraws have been re-issued
<MagicalTux> just spent one week of BTC-only income

MagicalTux is a dev of MtGox.

[tvbcof]

Maybe this helps.
It seems MtGox made a mistake somewhere.

<MagicalTux> that's a problem, but not the worst problem we ever faced
<MagicalTux> all the broken withdraws have been re-issued
<MagicalTux> just spent one week of BTC-only income

MagicalTux is a dev of MtGox.

Damn.  A quick peek at bitcoincharts and back-of-the-envelope calc after my above note lead me to believe that they could make it back in a week.  More luck than any real understanding though.

[worldinacoin]

All these bitcoins, can they be retrieved or is it "Sayonara" for them?  That's really a lot of money!