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 attacker address, tricking users into RBF fee-bumping and signing it.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/spesmilo/electrum/commit/90fe30822561e515a9d2d6e5a352cc07780999eb
https://github.com/spesmilo/electrum/security/advisories/GHSA-6jp4-8v48-cc5v
https://www.vulncheck.com/advisories/electrum-before-4.8.3-missing-signature-verification-of-mempool-transactions

Configurations

No configuration.

History

27 Oct 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-27 14:16

Updated : 2026-10-28 17:18

NVD link : CVE-2026-117601

Mitre link : CVE-2026-117601

CVE.ORG link : CVE-2026-117601

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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