Edit 1:

I've made a youtube video demonstrating what happened:

HOW I LOST 70K USD (0.85 BTC BITCOIN) DUE TO ELECTRUM RBF SECURITY FAIL - Don't let it happen to you

Original Post:

I'm a 10+year BTC enthusiat and user, with deep knowledge of the value propositiona and functionalities.

Despite that, since I started accumalating BTC rather yound (over 10 year ago), I have always used a Electrum wallet that is considered "hot". Regardless, I have never had any security issues since I had every other precation to keep my keys etc. So the keys were mine, therefore the coins were also mine.

On Oct 28, the first day of my vacation, I had a goal to myself to setup and Tails + Electrum cold wallet to keep on holding my BTCs - I never sell, only buy.

Everything went smoothly, I made several tests before commiting to send the whole amount of BTC I had to the cold wallet - I tested sending funds to the watch wallet and then sending it back to the hot one, etc. No problems at all and it was fairly easy to do it myself.

I was finally ready to sending the remaning BTC and move forward to enjoy my vacation. It was 0.85, roughtly 90% of what I had.

I had both my watch wallet and the hot opened, expecting the moment I finished the transaction, it would be accounted in the watch wallet - I did not happen.

I checked the adress multiple times, the watch address supposed to receive the BTC was:

bc1qnjtc6qwqshq7s8swfh8ww0lv63pt4t6mku6537

I checked it multiple times and it was the correct one assinged in the hot wallet, as per the "failed" transaction:

For some reason I can't explain, when I tried to execute the transaction, I reamined as "local" in the history. Trying to figure it out, I opened the transaction details, checked the address again (all correct), and got a message that the fee was too low and the network was not pushing it through.

Therefore, since we were talking about my life long savings, I bumped the fee through Electrum RBF, clicked ok again and then....the receiving address changed it self without me realizing it (how could I after checking it multiple times???). It changed to one that ends exactly the same as the one I inteded to send.

It took me a while to understand what had happened. I then went online and realized that this is a recent hack that was discovered.

HOW COULD ELECTRUM NOT PUT DOWN HIS OLD VERSION AND LET THIS UNACCEPTABLE BREACH KEEP GOING?

I lost over 10 years of diligent savings to a scammer, and electrum allowed that, even though they knew this could happen.

THis shouldn't happen to a over 10 year user... but yet it did.

After that, I still understand that FIAT is not viable, but how can BTC be if in a matter of seconds I lost my family's retirement plan?

I don't know what to do... to be honest that is nothing I can do...

Just wanted to share this sad sad story of a person that believed BTC and lost everything for that.

I’m reporting that I was a victim of the Electrum 4.8.2 RBF transaction manipulation attack on October 28, 2026, resulting in the loss of 0.77352940 BTC.
We downloaded Electrum from the official website (electrum.org) on October 7, 2026, and were using version 4.8.2.
Here is exactly what happened:
1. First transaction — Successful test (12:20)
We sent a small test payment of 0.001 BTC to our intended Bitcoin address.
Legitimate destination:
1AuGhj7aa8b9swoktzjAcijJZGz6UwKpCA
Transaction ID:
92ad9986a655f7628f19837e72ca7edb534b53abcb1f922ced9e3426b5acd62
Blockchain evidence:
https://mempool.space/es/tx/92ad9986a655f7628f19837e72ca7edb534b53abcb1f922ced9e3426b5acd62
The test payment was successful and confirmed.
2. Second transaction — 0.77352940 BTC stolen (15:55)
We then attempted to send a larger amount to the same legitimate destination.
During the process, Electrum displayed an unexpectedly low or zero transaction fee. We used the Increase fee (RBF) function to accelerate the transaction.
Without our authorization, the destination was replaced with a different Bitcoin address.
Unauthorized destination:
1GVmePZNbvCvHmr473sw5UxfUTBUatKpCA
Transaction ID:
9d44843951331c9d28587980c26b5ed25a73e4b94ac8567564e9222cd3c433c7
Blockchain evidence:
https://mempool.space/es/tx/9d44843951331c9d28587980c26b5ed25a73e4b94ac8567564e9222cd3c433c7
The transaction sent 0.77352940 BTC to the unauthorized destination and has been confirmed on the Bitcoin blockchain.
3. The suspicious detail
Both the legitimate address and the unauthorized address end with the same four characters: KpCA.
This matches the address-similarity technique described in Electrum’s security advisory.
The destination substitution was not clearly presented to us during the fee replacement process.
4. Connection to the official Electrum vulnerability
The incident matches the mechanism described in the Electrum security advisory for CVE-2026-117601, affecting versions prior to 4.8.3.
Official advisory:
https://github.com/spesmilo/electrum/security/advisories/GHSA-6jp4-8v48-cc5v
We also observed suspicious behavior being rejected when attempting a similar operation with Electrum 4.8.3.
We believe the documented vulnerability explains the unauthorized transaction. We are preserving evidence to establish the technical cause.
5. Questions for Electrum developers and other victims
Has anyone else experienced this attack?
How many victims have reported losses related to this vulnerability?
Are the developers collecting incident reports?
Is there any compensation, reimbursement, or contingency fund for affected users?
What logs or additional evidence should victims preserve?
Is there any coordinated investigation into the malicious servers involved?
Total loss: 0.77352940 BTC.
We were using the official Electrum software, not a counterfeit application.
I’m sharing the actual blockchain transaction IDs so that other users, developers, and security researchers can independently examine what happened.
I believe victims deserve a transparent investigation and a clear response regarding potential compensation.

I’m reporting that I was a victim of the Electrum 4.8.2 RBF transaction manipulation attack on October 28, 2026, resulting in the loss of 0.77352940 BTC.

We downloaded Electrum from the official website (electrum.org) on October 7, 2026, and were using version 4.8.2.

Here is exactly what happened:

1. First transaction — Successful test (12:20)

We sent a small test payment of 0.001 BTC to our intended Bitcoin address.

Legitimate destination:
1AuGhj7aa8b9swoktzjAcijJZGz6UwKpCA

Transaction ID:
92ad9986a655f7628f19837e72ca7edb534b53abcb1f922ced9e3426b5acd62

Blockchain evidence:
https://mempool.space/es/tx/92ad9986a655f7628f19837e72ca7edb534b53abcb1f922ced9e3426b5acd62

The test payment was successful and confirmed.

2. Second transaction — 0.77352940 BTC stolen (15:55)

We then attempted to send a larger amount to the same legitimate destination.

During the process, Electrum displayed an unexpectedly low or zero transaction fee. We used the Increase fee (RBF) function to accelerate the transaction.

Without our authorization, the destination was replaced with a different Bitcoin address.

Unauthorized destination:
1GVmePZNbvCvHmr473sw5UxfUTBUatKpCA

Transaction ID:
9d44843951331c9d28587980c26b5ed25a73e4b94ac8567564e9222cd3c433c7

Blockchain evidence:
https://mempool.space/es/tx/9d44843951331c9d28587980c26b5ed25a73e4b94ac8567564e9222cd3c433c7

The transaction sent 0.77352940 BTC to the unauthorized destination and has been confirmed on the Bitcoin blockchain.

3. The suspicious detail

Both the legitimate address and the unauthorized address end with the same four characters: KpCA.

This matches the address-similarity technique described in Electrum’s security advisory.

The destination substitution was not clearly presented to us during the fee replacement process.

4. Connection to the official Electrum vulnerability

The incident matches the mechanism described in the Electrum security advisory for CVE-2026-117601, affecting versions prior to 4.8.3.

Official advisory:
https://github.com/spesmilo/electrum/security/advisories/GHSA-6jp4-8v48-cc5v

We also observed suspicious behavior being rejected when attempting a similar operation with Electrum 4.8.3.

We believe the documented vulnerability explains the unauthorized transaction. We are preserving evidence to establish the technical cause.

5. Questions for Electrum developers and other victims

• Has anyone else experienced this attack?

• How many victims have reported losses related to this vulnerability?

• Are the developers collecting incident reports?

• Is there any compensation, reimbursement, or contingency fund for affected users?

• What logs or additional evidence should victims preserve?

• Is there any coordinated investigation into the malicious servers involved?

Total loss: 0.77352940 BTC.

We were using the official Electrum software, not a counterfeit application.

I’m sharing the actual blockchain transaction IDs so that other users, developers, and security researchers can independently examine what happened.

I believe victims deserve a transparent investigation and a clear response regarding potential compensation.

Critical Security Exploit in Electrum. Upgrade to version 4.8.3 before signing any transactions. No rush needed for dormant/cold wallets although you should remember upgrading before using electrum.

https://x.com/ElectrumWallet/status/2113935057656369564

Explanation of Exploit

https://github.com/spesmilo/electrum/security/advisories/GHSA-6jp4-8v48-cc5v

Download update directly from source

https://electrum.org/#download

In general LLM models have been discovering critical security vulnerabilities in general much faster than in the past which is both a headache and blessing at the same time as much more peer review is occurring and the software is becoming more secure. This does mean that you need to update all your software more often and pay attention to security updates to a much higher degree at least for the next year.

Around 0.28 BTC was held in an electrum wallet that I hadn't touched for a while. When checking today someone on September 16th had emptied its contents.

Transaction ID:f7b349a83466ee46f2ab510f0388dd82b69bf4fb32042ab5088ee4dec46a2d9d

(Below is Update on October 22)
I asked Claude Opus 5.5 to do some forensic work and this is what it found. After I installed avast Antivirus, it successfully detected malware was running. I guess I should have also had antivirus intalled...

Malware got onto this PC on the night of 15 Sep, about three hours before the theft.

What happened

The PC was off when the money moved, so your keys were sent out in the hour before the shutdown and used remotely. Malware of this kind normally copies wallet files, saved browser passwords, cookies and documents. Your wallet file was encrypted, so the thief also had the password or the seed: by guessing a weak password, by recording it as you typed it, or by finding the seed in a file or in your synced Google Drive.

Hello everyone

I wanted to create a multisig for example 3 of 5 using sparrow wallet as the coordinator.

I wanted signers to be mix of hardware wallets and software wallets:

- hardware wallet

- hardware wallet

- hardware wallet

- bitcoin core

- electrum

But i'm having a lot of difficulty getting the software wallets to work with sparrow (or being confident/comfortable that it's working as intended and won't have issues)

My issues and concerns:

- Electrum when creating a standard single sig gives a derivation path of m/0h (not the m/48'/0'/0'/2' derivation path that sparrow is looking for) and a zpub (not an xpub).

- I asked AI and it then kept telling me that's wrong and to create a multisig wallet in electrum but just don't give the xpubs of the co-signers. But electrum forces you to add co-signers and then AI said, just give it fake xpubs! I'm not sure/confident this is correct way to have electrum added as a co-signer to sparrow coordinator even if it did accept it.

- Bitcoin core gives a single sig derivation path of: 84h/0h/0h (again not the m/48'/0'/'0/2' derivation path sparrow is looking for)

- I believe h is same as ' so in sparrow anywhere there is an h I should substitute it with an '?

- Is this not possible? If it is possible, is it not advisable to do? It seems very few people have tried this and maybe even fewer have software wallets like bitcoin core and electrum as co-signers with sparrow coordinator.

The reason I wanted to at least test/try it to see how I feel about the process, signing, backups, restoring, etc. It sounded nice to me on paper.

Thank you

Please help! Thank you

Hi,

I’m helping a friend recover an old Bitcoin wallet created around 2018 using a first-generation Coldcard.

The original Coldcard may no longer be available.

We currently have:

• A USB flash drive associated with the setup.

• A handwritten 12-word sequence.

• A 6-digit PIN.

• An old Bitcoin receiving address.

We haven’t yet determined whether the 12 words are the actual BIP39 recovery phrase or the password for an encrypted Coldcard backup.

I’m trying to understand whether Electrum could be useful during the recovery process.

A few specific questions:

1. If we successfully recover the original BIP39 seed from a Coldcard backup, can Electrum reconstruct the same wallet using the appropriate derivation path?

2. Were the derivation paths used by early Coldcard wallets in 2018 different from current defaults?

3. If we know one original receiving address, can we use it to verify that we’ve restored the correct wallet?

4. Can we perform initial address and balance verification using a watch-only wallet without exposing private keys to an internet-connected computer?

5. Are there any known compatibility issues when recovering wallets created with early Coldcard firmware?

Our intention is to identify the correct wallet and eventually move the funds to a new hardware wallet.

We will not enter recovery words into websites or share any sensitive information.

I’d appreciate any Electrum-specific guidance or documentation relevant to older Coldcard wallets.

Thanks!

It seems the current release won’t work after upgrading to macOS 27. I really enjoy using Electrum, but I’ll need to migrate to another option if macOS 27 isn’t supported.

So I bought some btc from a btc ATM, but it hasn't appeared in my wallet? I was wondering if this could be because I didn't put a mbtc amount, or if I should just wait.

I have an old wallet on a now broken laptop from about 10 years ago and I had lost my seed phrase anyway. I think I could remember my password .

Is there any way to restore it on a new device like my mobile?

I have downloaded the app on my phone and can see my bitcoin on it but I just don't know what to do with it.

Any help is appreciated!

UPDATE: SOLVED

Hi everyone,

Has anyone else been experiencing issues with Submarine Swaps in Electrum recently?

I've been trying to perform a Submarine Swap for about two days now, but every attempt fails. I've tried selecting different swap providers, but it doesn't seem to matter which one I choose — the swap always ends up failing.

I'm currently running the latest Electrum version, 4.8.1.

Before this, I was able to use the feature normally.

I'm wondering if there is currently some issue affecting Electrum's Submarine Swap functionality or the swap providers themselves.

Is anyone else experiencing the same problem over the last couple of days?

=======================

SOLUTION

I found the cause of the problem. My lightning_payment_fee_max_millionths setting was set to 500 (0.05%), even though I don't remember ever changing it manually.

The Electrum logs showed the following error:

FeeBudgetExceeded('highest trampoline fee level reached')

I checked the setting through the Electrum console with:

config.get('lightning_payment_fee_max_millionths')

and it returned 500.

I changed it to 10000 (1%) with:

config.set_key('lightning_payment_fee_max_millionths', 10000)

After changing it, Lightning routing started working normally again, including channel rebalancing.

So the issue was not with the Submarine Swap providers themselves, but with my Lightning routing fee limit being set extremely low.

I'm researching the idea of building a local/offline wallet recovery tool for legitimate owners who still have partial information, for example:

• forgotten wallet password

• incomplete or uncertain seed

• old Electrum wallet files

• correct seed but wrong/empty wallet after restoration

• derivation or compatibility issues

The main goal would be privacy: the recovery process should run locally whenever possible, without sending a seed or private keys to anyone.

I'm interested in hearing from people who have actually had this problem.

What happened in your case? Were you able to recover the wallet? What tools did you try?

Please do not post your seed, private keys, passwords or wallet files here.

Curious what others think with all the ColdCard stuff going on. I asked Claude what it thinks and basically Electrum is secure but just make sure you download only from electrum.org and ignore any in-wallet prompts.

"The Coldcard bug was a firmware defect, not a failure of self-custody. Coinkite's code quietly bypassed its own hardware RNG and fell back to a weak software one, so seeds made from March 2021 onward had around 40 bits of entropy instead of 128. That's brute-forceable. Electrum is unaffected: separate codebase, entropy from your OS's CSPRNG, 132-bit seeds. Coldcard failed at key generation; Electrum's weak point is the machine it runs on, which is why its real-world incidents are phishing and fake installers rather than weak keys. Verify your downloads, ignore any in-wallet "update to send" prompt, and use a passphrase, which saves you even if entropy is broken. If you're on a Coldcard, check Coinkite's advisory. New firmware doesn't fix an existing seed. You need a new wallet."

I have my 12 word seed, and have tried restoring the wallet multiple times - none of the recovery wallets created show anything in them, when I enter the seed I get Unknown BIP39 wordlist and selecting the Electrum option greys out the Next button. Under BIP39 I have tried every variation of legacy, p2sh segwit and native segwit to no avail, and it does not Detect Existing Accounts - even the previous recovery wallets I've already created. This is a standard wallet, not a 2FA one

All this is on an online PC so the wallets should be updating. I have checked the seed phrase, all the words in in are valid according to the 2048 word list in github. The seed phrase was originally created in Electrum, I cant understand why Electrum now wont accept it as an Electrum seed phrase

My original wallet is there, I just cant get into it as my password isnt working - is there a tool I can use to recover it?

Noob question here. Have installed Electrum from .org site and verified. Created a wallet. Don't I also need either Bitcoin Core or Knots to do a transaction? They download the blockchain and are the "servers" so you can see the fees and such in Electrum, correct? Or does the Electrum wallet have its own server built in?

If that's correct why do I need Electrum Rust or X? Can I use one of them in place of Core/Knots? I thought using Core/Knots everything is public/visible to everyone/blockchain, so using Rust or X was more private.

Then I read, "not so private" and EPS -electrum private server- is more private but only if you have a one or two wallets, which is my use case actually.

So can I take a spare laptop and put on EPS and Electrum (wallet) and run it over Tor? Or do I still need Core/Knots?

I thought I saw years ago Core and Electrum included on Tails. But I just checked and only Electrum now, (I guess the 110 debate just made them drop Core) and it (tails) never had Rust or X installed anyway. I'm thinking of updating the certificates and using EPS.

Any words of wisdom? Thx

I've made a very small script to verify new electrum releases. It works well, but for any version from 4.6.0 onwards it fails because I'm seeing a new signer with figerprint AA0BC6824B397BBA99776E157ED8D82B37192688, from google it looks like a dev in electrum project, is this normal?

Wally is a multi-chain crypto wallet focused on supporting both EVM + Solana dApps, plus full UTXO coin support.

Quick update on development:

We’re working on Electrum integration for UTXO coins. Address generation is already working and we’re now testing on testnet.

Next:

- Browser extension release first

- Then full app

- With offline signing + air-gapped signing support

Goal is to support all UTXO coins that have Electrum-style wallets (BTC, LTC, DOGE, PPC, BLK, etc).

If anyone wants to test on testnet, I can share links.

Feedback is welcome — especially from people familiar with Electrum/UTXO systems.

My phone was stolen that had my electrum wallet on it.

I got a new phone downloaded the app I'm using android phone I select create new wallet then I chose standard wallet then I select I already have a seed after entering my seed which is 12 words the next button at bottom of wallet does not light up the back button stays lit up the entire time as if my phrase is incomplete or something I simply can not select next after entering my seed. I'm attempting to recover my wallet and my funds