CVE-2026-106582

Publication date 7 October 2026

Last updated 8 October 2026

Ubuntu priority

Cvss 3 Severity Score

Description

In sshd and ssh in OpenSSH before 10.6, an LZ77 dictionary coder can be used even though this is contraindicated by the arXiv 2609.07709 "Crossing the Streams" findings.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
openssh	26.04 LTS resolute	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Needs evaluation
openssh-ssh1	26.04 LTS resolute	Ignored
	24.04 LTS noble	Ignored
	22.04 LTS jammy	Ignored
	20.04 LTS focal	Ignored
	18.04 LTS bionic	Ignored
openssh-gssapi	26.04 LTS resolute	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release

Notes

mdeslaur

openssh-ssh1 is only provided for compatibility with old devices that cannot be upgraded to modern protocols. We will not be providing any security support for the openssh-ssh1 package as it is insecure and should be used in trusted environments only.

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
openssh	Upstream: 1d5340f

Severity score breakdown

CVSS version: CVSS v3.0

Base score 3.7 · Low

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality impact	Low
Integrity impact	None
Availability impact	None

Scores

Parameter	Value
Base score	3.7 · Low
Exploitability score	-
Impact score	-

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