CVE-2026-39834

Name	CVE-2026-39834
Description	When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.
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)
Debian Bugs	1137516

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
golang-go.crypto (PTS)	bullseye	1:0.0~git20201221.eec23a3-1	vulnerable
	bookworm	1:0.4.0-1	vulnerable
	trixie	1:0.25.0-1	vulnerable
	forky, sid	1:0.52.0-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
golang-go.crypto	source	(unstable)	1:0.52.0-1			1137516

Notes

[bullseye] - golang-go.crypto <postponed> (Limited support, follow bookworm DSAs/point-releases)
https://www.openwall.com/lists/oss-security/2026/05/22/6
https://github.com/golang/go/issues/79567