CVE-2026-39834

critical

Published 2026-05-22 · Modified 2026-05-27

CVSS v3

9.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

CVSS v2

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VIR risk

9.1

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.

Predictions

Exploit likelihood

94%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2026-39834.html

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2026-39834

OS impact

OS	Version	Status	Fixed in
debian	bookworm	affected
debian	bullseye	affected
debian	forky	affected
debian	sid	fixed	`1:0.52.0-1`
debian	trixie	affected
sles		affected

Package impact

Ecosystem	Package	Vulnerable	Fixed
Go	golang.org/x/crypto	`<0.52.0`	`0.52.0`

References

Verify integrity in audit chain (admin only). AS-IS.