Electrum: Malicious server can replace a just-broadcast tx and try to trick user into RBF-ing it

Summary The main Electrum server the client connects to is trusted with mempool "unconfirmed" transactions. This is documented design. 0 However now someone figured out a way to practically exploit it: - when the client broadcasts a new tx1, a malicious server can swallow it, - and update the...

GHSA-6JP4-8V48-CC5V Electrum: Malicious server can replace a just-broadcast tx and try to trick user into RBF-ing it

Summary The main Electrum server the client connects to is trusted with mempool "unconfirmed" transactions. This is documented design. 0 However now someone figured out a way to practically exploit it: - when the client broadcasts a new tx1, a malicious server can swallow it, - and update the...

CVE-2026-117601

Versions of Electrum before 4.8.3 are vulnerable to a flaw where the software fails to verify signatures of wallet-owned inputs in unconfirmed mempool transactions. This allows malicious servers to replace a recently broadcast transaction with a conflicting one. An attacker can effectively

CVE-2026-117601 Electrum before 4.8.3 Missing Signature Verification of Mempool Transactions

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...

CVE-2026-117601

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...

CVE-2026-117601 Electrum before 4.8.3 Missing Signature Verification of Mempool Transactions

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...

rbfasesores.com Cross Site Scripting vulnerability OBB-3178885

Following the coordinated and responsible vulnerability disclosure guidelines of the ISO 29147 standard, Open Bug Bounty has: a. verified the vulnerability and confirmed its existence; b. notified the website operator about its existence. Technical details of the vulnerability are currently hidde...

Code injection

Samourai Wallet Stonewallx2 0.99.98e allows a denial of service via a P2P coinjoin. The attacker and victim must follow each other's paynym. Then, the victim must try to collaborate with the attacker for a Stonewallx2 transaction. Next, the attacker broadcasts a tx, spending the inputs used in...

CVE-2020-12119

Ledger Live before 2.7.0 does not handle Bitcoin's Replace-By-Fee RBF. It increases the user's balance with the value of an unconfirmed transaction as soon as it is received before the transaction is confirmed and does not decrease the balance when it is canceled. As a result, users are exposed t...

CVE-2020-12119

Ledger Live before version 2.7.0 is affected by an RBF handling flaw: unconfirmed Bitcoin transactions are credited to the user’s balance upon receipt and not deducted if canceled, enabling basic and amplified double-spending and potential DoS attacks without user consent. The vulnerability is do...