CVE-2026-117601

Name	CVE-2026-117601
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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
electrum (PTS)	bookworm	4.3.4+dfsg1-1+deb12u1	vulnerable
	trixie	4.5.8+ds-6	vulnerable
	forky	4.8.1+dfsg-1	vulnerable
	sid	4.8.3+dfsg-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
electrum	source	(unstable)	4.8.3+dfsg-1

Notes

https://github.com/spesmilo/electrum/security/advisories/GHSA-6jp4-8v48-cc5v
Fixed by: https://github.com/spesmilo/electrum/commit/16e7102bce4ce34c28ce094bf34bec2489283fbf (4.8.3)
Fixed by: https://github.com/spesmilo/electrum/commit/99131b132925fdc4803e77e45fd939cf8236749a (4.8.3)
Fixed by: https://github.com/spesmilo/electrum/commit/9bbc139f7a5a33cf84cc73867172d5584a9ce2f1 (4.8.3)