Electrum before 4.8.3 Missing Signature Verification of Mempool Transactions
- Published
- Last modified
- Status
- published
- Known exploitation
- Not listed in CISA KEV
- Fix
- Fixed in 4.8.3
- Public exploit
- None on Exploit-DB
Summary
Electrum, a Bitcoin wallet application, is affected, and a malicious server connected to it can trick users into signing a replacement transaction that sends their funds to an attacker instead of the intended recipient. This can result in the loss of bitcoin without the user realizing that their original transaction was swapped out.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
Electrum before 4.8.3 fails to verify signatures of wallet-owned inputs in unconfirmed mempool transactions, allowing malicious servers to replace a just-broadcast transaction with a conflicting one. Attackers can swallow the user's transaction and display an invalid zero-fee copy paying an attacker address, tricking users into RBF fee-bumping and signing it.
Affected versions
- spesmilo electrum
fixed in 4.8.3