Author

Topic: Namecoin appears to be under a 51% attack (80% of the hashpower) (Read 1277 times)

legendary
Activity: 1708
Merit: 1020
This is indeed BTC-Guild. Their transaction selection is not working as it should, often dropping transactions. This has been confirmed by Eleuthria. I will ask him to fix it once we have released the next, hopefully more stable version of Namecoin.

Snailbrain & co are currently working on some smaller updates and fixes for the new Namecoin-Qt. After that we will do some more testing, probably come up with a release candidate. So the next official release can be expected within a month or so.
hero member
Activity: 541
Merit: 500
My guess is that tremor in the force is the BTC-Guild pool, I think it's been about 2 months or so since they started merge mining NMC.
sr. member
Activity: 476
Merit: 253
That is the main problem of mergemining. It is so easy for pool operators to 51% it that it has to happen.
member
Activity: 89
Merit: 77
Don't a lot of pools co-mine BTC and NMC?  It seems like you'd need an ungodly amount of hashing power to pull a 51% attack.  You'd have to outgun entire pools.
Yes, that's why it seems likely that a pool is doing it.
full member
Activity: 168
Merit: 100
Don't a lot of pools co-mine BTC and NMC?  It seems like you'd need an ungodly amount of hashing power to pull a 51% attack.  You'd have to outgun entire pools.
member
Activity: 89
Merit: 77
Here's a chatlog from the #namecoin channel... couldn't find anything about this on the forums already, sorry if I missed something:

Quote
[2013-08-15 10:19:28] okay, so the last 6 blocks have had no transactions in them... anyone know why that might be happening?
[2013-08-15 10:20:11] no idea, maybe try to message DrHaribo, he should be on freenode and operates Bitminter
[2013-08-15 10:20:29] are there no transactions waiting?
[2013-08-15 10:21:11] it actually seems to be fairly common... looking at the explorer, it's common for there to be 6 or so blocks with nothing, and then like 20-30 transactions in the next block
[2013-08-15 10:21:27] I'm pretty sure that's statistically not by random chance
[2013-08-15 10:21:29] so, some miners aren't doing anything?
[2013-08-15 10:21:47] that's what it looks like to me
[2013-08-15 10:21:51] but I'm not an expert
[2013-08-15 10:22:38] well i know i'm mining namecoin, but i have no idea what my pool operator's doing
[2013-08-15 10:22:51] ok, my transaction just got into a block about 10 seconds ago
[2013-08-15 10:22:57] even though it was sent an hour ago
[2013-08-15 10:23:11] and there were 158 tx's in this new block
[2013-08-15 10:23:17] so a lot of people were waiting
[2013-08-15 10:23:32] hmm
[2013-08-15 10:23:36] that doesn't sound good
[2013-08-15 10:23:47] agreed
[2013-08-15 10:24:00] do you think it's possible to track down which miners were responsible for the last few blocks?
[2013-08-15 10:24:14] no idea
[2013-08-15 10:25:11] I can see their 50NMC tx's to themselves... so we could probably track down the miners via blockchain analysis that way
[2013-08-15 10:25:15] but that sounds like a lot of work
[2013-08-15 10:26:46] that one miner seems to get a ton of the blocks, and doesn't do any transactions...
[2013-08-15 10:26:55] N4BbUHfarRXx8GBNj9DHAqthhuvxsKpnZE
[2013-08-15 10:27:04] wohoha okay, i wanted to see if my pool had minted that 158 tx block, and nope  : we're at 100M PoW and 99.25% CDF, mining for 7 hours
[2013-08-15 10:27:24] lol
[2013-08-15 10:31:55] |<-- knotwork has left freenode (Read error: Connection timed out)
[2013-08-15 10:32:25] -->| knotwork (~markm@unaffiliated/knotwork) has joined #namecoin
[2013-08-15 10:47:51] -->| SwiftDK (redacted) has joined #namecoin
[2013-08-15 10:53:16] of the last 15 blocks, only 3 have any transactions
[2013-08-15 10:54:25] |<-- X-Rob has left freenode (Read error: Connection reset by peer)
[2013-08-15 10:54:35] -->| X-Rob (~Rob7@unaffiliated/x-rob) has joined #namecoin
[2013-08-15 10:55:30] -->| domob (redacted) has joined #namecoin
[2013-08-15 10:55:50] and all 12 of the empty blocks are by the same miner
[2013-08-15 10:56:01] I believe that would make this a 51% attack?
[2013-08-15 10:58:43] is there any way to track down the miner's identity from his payment address?  I'm wondering if it's a pool or a freelancer
[2013-08-15 10:59:14] whoever it is probably has the ability to reverse transactions / steal names if I understand the implications of a 51% attack
[2013-08-15 11:05:51] ah but
[2013-08-15 11:06:00] only the current transactions
[2013-08-15 11:06:17] if he wants to screw old transactions, he has to rehash each of the blocks
[2013-08-15 11:06:30] AND keep up
[2013-08-15 11:06:44] he has 80% of the hashpower, that sounds quite doable for names that were registered recently
[2013-08-15 11:06:57] he has waitwut ?
[2013-08-15 11:07:18] 12 of the last 15 blocks have their mining payout to the same Namecoin address, i.e. the same miner
[2013-08-15 11:08:53] I think this is a Bad Thing (TM)
[2013-08-15 11:09:28] i hope it's a bug in a pool and will get fixed soon
[2013-08-15 11:09:29] oh yes it is
[2013-08-15 11:10:01] namecoin is a solution to so many problems
[2013-08-15 11:10:46] I wonder how long this attack has been going on... anyone want to look through the block explorer and see how long he's had this much of the hashpower?
[2013-08-15 11:12:33] |<-- c0rw1n has left freenode (Remote host closed the connection)
[2013-08-15 11:15:32] received 6609 payouts since 12/06/13 02:26:56 (didn't check if all are generations but the vast majority seems to be 50nmc exactly)
[2013-08-15 11:16:15] |<-- domob has left freenode (Ping timeout: 276 seconds)
[2013-08-15 11:18:14] -->| domob (redacted) has joined #namecoin
[2013-08-15 11:19:19] makes you wonder what they'd want to do it for... I mean, it's not really a very logical attack
[2013-08-15 11:19:45] most likely they set up merged mining incorrectly or something
[2013-08-15 11:19:48] crap, so over the past 9 weeks he's averaged 71% of the hashpower
[2013-08-15 11:19:59] ...
[2013-08-15 11:20:30] and the difficulty isn't low either, so they must be one of the mining pools
[2013-08-15 11:21:06] if it's a pool, then one of the pool's users should be able to trace his 50NMC generation to their payout, right?
[2013-08-15 11:22:00] true
[2013-08-15 11:22:17] are there any tools for tracing transactions?
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