paymentrequest.py in Electrum before 4.2.2 allows a file:// URL in the r parameter of a payment request (e.g., within QR code data). On Windows, this can lead to capture of credentials over SMB. On Linux and UNIX, it can lead to a denial of service by specifying the /dev/zero filename.

The Python console in Electrum through 2.9.4 and 3.x through 3.0.5 supports arbitrary Python code without considering (1) social-engineering attacks in which a user pastes code that they do not understand and (2) code pasted by a physically proximate attacker at an unattended workstation, which makes it easier for attackers to steal Bitcoin via hook code that runs at a later time when the wallet password has been entered, a different vulnerability than CVE-2018-1000022.