Recovering funds from misconfigured channel

[dddd-rgb]

Hi,

I tried to open a channel with Bitrefill's node (030c3f19d742ca294a55c00376b3b355c3c90d61c6b6b39554dbc7ac19b141c14f) using the low level command fundchannel_start.

I got a Taproot multi-sig address as seen in the command output:

lightning-cli fundchannel_start 030c3f19d742ca294a55c00376b3b355c3c90d61c6b6b39554dbc7ac19b141c14f 1189676
{
   "funding_address": "bc1qtajsfaeftl3wmcpe7vg8rajg6p5dl38w6w47k38clczkr5p23dasgkgwfj",
   "scriptpubkey": "00205f6504f7295fe2ede039f31071f648d068dfc4eed3abeb44f8fe0561d02a8b7b",
   "channel_type": {
      "bits": [
         12,
         22
      ],
      "names": [
         "static_remotekey/even",
         "anchors/even"
      ]
   },
   "warning_usage": "The funding transaction MUST NOT be broadcast until after channel establishment has been successfully completed by running `fundchannel_complete`"
}

And I did send the funds to this address as you can see in the blockchain. But the channel never locked in, even after sufficient confirmations.

Also, I noticed that the funding_txid is in the listpeerchannels is different from the actual transaction ID in the blockchain.

I'm not sure what went wrong. But there are few options:

1. I broadcast the funding transaction before fundchannel_complete, but I think I did it correctly or my memory betray me.
2. I made multiple try with fundchannel_start (and fundchannel_cancel), before sending the funds. So maybe I used wrong old fund address. But according to the console log it's the last address I got.
3. I used legacy P2PKH UTXO as an input in the funding transaction. I thought maybe I should use SegWit only?

I talked with the peer owner, aka Bitrefill, and they are willing to collaborate and help recover this funds from this multisig wallet between us, if we can figure out how and if we can recover it.

Is it possible in anyway to recover these funds?

Thanks

[kallerosenbaum]

Kalle at Bitrefill here (the other side of the incomplete channel). We run LND. We'd very much appreciate some help in figuring this out.

Here's what the pending channels with @dddd-rgb's node looks like on our node (none of which matches the funding tx 51643ba3bf3e266d308461c8bf6e941280c7dc58bc71d5d9b3b87a71d9aaa811):

$ lncli pendingchannels
...
    "pending_open_channels": [
        {
            "channel": {
                "remote_node_pub": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
                "channel_point": "b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0",
                "capacity": "1189676",
                "local_balance": "0",
                "remote_balance": "1187611",
                "local_chan_reserve_sat": "11896",
                "remote_chan_reserve_sat": "11896",
                "initiator": "INITIATOR_REMOTE",
                "commitment_type": "ANCHORS",
                "num_forwarding_packages": "0",
                "chan_status_flags": "",
                "private": false,
                "memo": "",
                "custom_channel_data": ""
            },
            "commit_fee": "1405",
            "commit_weight": "772",
            "fee_per_kw": "1250",
            "funding_expiry_blocks": 490,
            "confirmations_until_active": 3,
            "confirmation_height": 0
        },
        {
            "channel": {
                "remote_node_pub": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
                "channel_point": "5f1f1c0b28858b5a175d249b523dad8f2ffa7b8720e2b54ee123ae3097009b5a:0",
                "capacity": "1509970",
                "local_balance": "0",
                "remote_balance": "1507905",
                "local_chan_reserve_sat": "15099",
                "remote_chan_reserve_sat": "15099",
                "initiator": "INITIATOR_REMOTE",
                "commitment_type": "ANCHORS",
                "num_forwarding_packages": "0",
                "chan_status_flags": "",
                "private": false,
                "memo": "",
                "custom_channel_data": ""
            },
            "commit_fee": "1405",
            "commit_weight": "772",
            "fee_per_kw": "1250",
            "funding_expiry_blocks": 529,
            "confirmations_until_active": 3,
            "confirmation_height": 0
        },
        {
            "channel": {
                "remote_node_pub": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
                "channel_point": "1161ca3a79b6aaa37e2a8f2376f29872c2e51897d56f26811639c106143e0ddf:0",
                "capacity": "1509970",
                "local_balance": "0",
                "remote_balance": "1507905",
                "local_chan_reserve_sat": "15099",
                "remote_chan_reserve_sat": "15099",
                "initiator": "INITIATOR_REMOTE",
                "commitment_type": "ANCHORS",
                "num_forwarding_packages": "0",
                "chan_status_flags": "",
                "private": false,
                "memo": "",
                "custom_channel_data": ""
            },
            "commit_fee": "1405",
            "commit_weight": "772",
            "fee_per_kw": "1250",
            "funding_expiry_blocks": 528,
            "confirmations_until_active": 3,
            "confirmation_height": 0
        },
...

Searching our logs for b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28 || 1db9f8d6831e16bb82c4889aa78a96cb5e880174b3aff6ed03647eb31dbe58ea (which is the channel that matches the amount of his fundchannel_start command:

2026-01-30 14:56:53.127 [INF] FNDG: Recv'd fundingRequest(amt=0.01189676 BTC, push=0 mSAT, delay=144, pendingId=1db9f8d6831e16bb82c4889aa78a96cb5e880174b3aff6ed03647eb31dbe58ea) from peer(0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488)
2026-01-30 14:56:53.196 [INF] FNDG: Requiring 3 confirmations for pendingChan(1db9f8d6831e16bb82c4889aa78a96cb5e880174b3aff6ed03647eb31dbe58ea): amt=0.01189676 BTC, push_amt=0 mSAT, committype=anchors-zero-fee-second-level, upfrontShutdown=
2026-01-30 14:56:53.196 [INF] FNDG: Sending fundingResp for pending_id(1db9f8d6831e16bb82c4889aa78a96cb5e880174b3aff6ed03647eb31dbe58ea)
2026-01-30 14:58:11.601 [INF] FNDG: completing pending_id(1db9f8d6831e16bb82c4889aa78a96cb5e880174b3aff6ed03647eb31dbe58ea) with ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0)
2026-01-30 14:58:11.622 [INF] FNDG: sending FundingSigned for pending_id(1db9f8d6831e16bb82c4889aa78a96cb5e880174b3aff6ed03647eb31dbe58ea) over ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0)
2026-01-30 14:58:11.626 [INF] CNCT: Creating new chainWatcher and ChannelArbitrator for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0)
2026-01-30 14:58:11.640 [INF] CNCT: ChannelArbitrator(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0): starting state=StateDefault, trigger=chainTrigger, triggerHeight=934353
2026-01-30 14:58:11.640 [INF] CNCT: Close observer for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0) active
2026-01-30 14:58:11.641 [INF] NTFN: New confirmation subscription: conf_id=473, txid=b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28, num_confs=3 height_hint=934353
2026-01-30 14:58:11.641 [INF] FNDG: Waiting for funding tx (b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28) to reach 3 confirmations
2026-01-30 14:58:11.643 [INF] NTFN: Historical spend dispatch finished for request outpoint=b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0, script=0 5f6504f7295fe2ede039f31071f648d068dfc4eed3abeb44f8fe0561d02a8b7b (start=934353 end=934353) with details: <nil>
2026-01-30 21:59:40.547 [WRN] CHBU: Replacing disk backup for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0) w/ newer version
2026-01-30 22:02:48.281 [WRN] CHBU: Replacing disk backup for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0) w/ newer version
2026-01-30 22:38:46.590 [WRN] CHBU: Replacing disk backup for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0) w/ newer version
2026-01-30 23:20:45.397 [WRN] CHBU: Replacing disk backup for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0) w/ newer version
2026-01-31 15:40:51.598 [WRN] CHBU: Replacing disk backup for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0) w/ newer version
2026-01-31 16:22:43.304 [WRN] CHBU: Replacing disk backup for ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0) w/ newer version
2026-01-31 16:24:23.458 [INF] PEER: Peer(0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488): Loading ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0), isPending=true
2026-01-31 16:24:23.459 [WRN] PEER: Peer(0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488): Unable to find our forwarding policy for channel b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0, using default values
2026-01-31 18:56:58.001 [INF] PEER: Peer(0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488): Loading ChannelPoint(b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0), isPending=true
2026-01-31 18:56:58.003 [WRN] PEER: Peer(0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488): Unable to find our forwarding policy for channel b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0, using default values

Searching the logs for 51643ba3bf3e266d308461c8bf6e941280c7dc58bc71d5d9b3b87a71d9aaa811 ==> no hits.

For completeness: There's also an active channel between us, but that's also another funding txid (and another capacity):

# lncli listchannels --peer=0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488
{
    "channels": [
        {
            "active": true,
            "remote_pubkey": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
            "channel_point": "b8322bdc95404f3f710877fdf4843851bcf10d64629a5abf99f79662b52c75a6:0",
            "chan_id": "a6752cb56296f799bf5a9a62640df1bc513884f4fd7708713f4f4095dc2b32b8",
            "scid": "1027379267084091392",
            "scid_str": "934396x2086x0",
            "capacity": "1509858",
            "local_balance": "2329",
            "remote_balance": "1505458",
            "commit_fee": "1411",
            "commit_weight": "1116",
            "fee_per_kw": "1255",
            "unsettled_balance": "0",
            "total_satoshis_sent": "0",
            "total_satoshis_received": "2329",
            "num_updates": "1742",
            "pending_htlcs": [],
            "csv_delay": 144,
            "private": false,
            "initiator": false,
            "chan_status_flags": "ChanStatusDefault",
            "local_chan_reserve_sat": "15098",
            "remote_chan_reserve_sat": "15098",
            "static_remote_key": false,
            "commitment_type": "ANCHORS",
            "lifetime": "53625",
            "uptime": "53577",
            "close_address": "",
            "push_amount_sat": "0",
            "thaw_height": 0,
            "local_constraints": {
                "csv_delay": 144,
                "chan_reserve_sat": "15098",
                "dust_limit_sat": "354",
                "max_pending_amt_msat": "18446744073709551615",
                "min_htlc_msat": "0",
                "max_accepted_htlcs": 30
            },
            "remote_constraints": {
                "csv_delay": 181,
                "chan_reserve_sat": "15098",
                "dust_limit_sat": "546",
                "max_pending_amt_msat": "1494760000",
                "min_htlc_msat": "1",
                "max_accepted_htlcs": 483
            },
            "alias_scids": [],
            "zero_conf": false,
            "zero_conf_confirmed_scid": "0",
            "peer_alias": "YELLOWTRINITY",
            "peer_scid_alias": "0",
            "memo": "",
            "custom_channel_data": ""
        }
    ]
}

[rustyrussell]

OK, what cln version is this for a start?

And curious: why use fundchannel_start etc not just fundchannel? Are you using an external wallet?

This is going to be really hard to track without knowing exactly what you did. If handed a PSBT to fundchannel_complete, then broadcast a different PSBT, which seems likely, you're in trouble.

[rustyrussell]

What is the output of listpeerchannels 030c3f19d742ca294a55c00376b3b355c3c90d61c6b6b39554dbc7ac19b141c14f ?

[rustyrussell]

I used legacy P2PKH UTXO as an input in the funding transaction. I thought maybe I should use SegWit only?

Yes. You CANNOT use a p2pkh with this interface. We never noticed because we never supported that in CLN :(

It might have worked if you signed the PSBT first before giving it to funchannel_complete, but if you didn't, the txid will change once you sign it, and you'll end up broadcasting a different tx from the one everyone is waiting for.

I will open an issue to detect (and refuse!) such PSBTs at fundchannel_start, if we can. That would have avoided this mess.

But the good news is that the latest version of chantools seems to support CLN for zombiechannels which is designed to work for this case:

https://github.com/lightninglabs/chantools/blob/master/doc/zombierecovery.md

And the general docs say for CLN "use --hsm_secret flag instead of root key or wallet.".

Caution: I have not used this tool before!

[kallerosenbaum]

Thanks a lot @rustyrussell.

@dddd-rgb I prefer not to run chantools on our end, because 1) I don't want to fiddle with our seed, and 2) We have so many keys to list in preparekeys (~20000),

But I figured out which key I need to use to sign the PSBT, so I have manually added the key information to the match file so you can run the zombierecovery makeoffer tool (Please shout if I got the format wrong somehow):

{
    "node1": {
        "identity_pubkey": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
        "contact": "belongs to @dddd-rgb"
    },
    "node2": {
        "identity_pubkey": "030c3f19d742ca294a55c00376b3b355c3c90d61c6b6b39554dbc7ac19b141c14f",
        "contact": "belongs to Bitrefill",
        "payout_addr": "bc1pm0avkcu5cr2dge7spyzwphl73qp8gxppagdyuragamqfy52revhs67nq5y",
        "multisig_keys": ["03815e9bcf4038e9bd5d566edd89b6ae8a866f79e95f025505bed963494b94fc6e"]
    },
    "channels": [
        {
            "chan_point": "b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0",
            "address": "bc1qtajsfaeftl3wmcpe7vg8rajg6p5dl38w6w47k38clczkr5p23dasgkgwfj",
            "capacity": 1189676
        }
    ]
}

I guess your next step is to call zombierecovery preparekeys with the following match.json file and other relevant flags:

{
    "node1": {
        "identity_pubkey": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
        "contact": "belongs to @dddd-rgb"
    },
    "node2": {
        "identity_pubkey": "030c3f19d742ca294a55c00376b3b355c3c90d61c6b6b39554dbc7ac19b141c14f",
        "contact": "belongs to Bitrefill"
    },
    "channels": [
        {
            "chan_point": "b7ec229791cd0dba9312a8be75e6213ff6c4c8e61e5b7d71148d05f57c4d5e28:0",
            "address": "bc1qtajsfaeftl3wmcpe7vg8rajg6p5dl38w6w47k38clczkr5p23dasgkgwfj",
            "capacity": 1189676
        }
    ]
}

This will fill in some key data in your json file. Then I think you should call

chantools zombierecovery makeoffer --node1_keys=<yourjsonfile> --node2_keys=<bitrefilljsonfile>

Looking forward to signing your PSBT!

[kallerosenbaum]

(@rustyrussell Please forgive us for exploiting your issue tracker as a channel close communication channel, but it's convenient and maybe someone might find it useful)

[kallerosenbaum]

Gahh, I gave the wrong txid to spend from. Sorry! My match.json should be

{
    "node1": {
        "identity_pubkey": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
        "contact": "belongs to @dddd-rgb"
    },
    "node2": {
        "identity_pubkey": "030c3f19d742ca294a55c00376b3b355c3c90d61c6b6b39554dbc7ac19b141c14f",
        "contact": "belongs to Bitrefill",
        "payout_addr": "bc1pm0avkcu5cr2dge7spyzwphl73qp8gxppagdyuragamqfy52revhs67nq5y",
        "multisig_keys": ["03815e9bcf4038e9bd5d566edd89b6ae8a866f79e95f025505bed963494b94fc6e"]
    },
    "channels": [
        {
            "chan_point": "51643ba3bf3e266d308461c8bf6e941280c7dc58bc71d5d9b3b87a71d9aaa811:0",
            "address": "bc1qtajsfaeftl3wmcpe7vg8rajg6p5dl38w6w47k38clczkr5p23dasgkgwfj",
            "capacity": 1189676
        }
    ]
}

And your match.json to run preparekeys with should be

{
    "node1": {
        "identity_pubkey": "0272e5a558b7bc9fa1f7e0cd42b6b237bbfdca71baf3300707b9562efed46ec488",
        "contact": "belongs to @dddd-rgb"
    },
    "node2": {
        "identity_pubkey": "030c3f19d742ca294a55c00376b3b355c3c90d61c6b6b39554dbc7ac19b141c14f",
        "contact": "belongs to Bitrefill"
    },
    "channels": [
        {
            "chan_point": "51643ba3bf3e266d308461c8bf6e941280c7dc58bc71d5d9b3b87a71d9aaa811:0",
            "address": "bc1qtajsfaeftl3wmcpe7vg8rajg6p5dl38w6w47k38clczkr5p23dasgkgwfj",
            "capacity": 1189676
        }
    ]
}

The only difference I've made is the chan_point property.

Can you please rerun you things with the new files? Thanks!

[kallerosenbaum]

Damn, this was harder than I thought, but it worked. Huge thanks @rustyrussell for the valuable input. Would not have realized that this was a case of "tx malleability" by myself.

@dddd-rgb here's the tx. Please confirm that you received the funds.
https://mempool.space/tx/6089b76456a4223a1e261a4248ccbd41ce25d950f8b2f306768a0fe8e2c38285

[dddd-rgb]

Yes, it worked! @kallerosenbaum thank you so much for the corporation!

I thought it might be tx malleability. I did this process few times but not with legacy input.

And thank you @rustyrussell for the support! 🙏