CVE-2026-35388 - Vulnerability Details - OpenCVE

OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing sessions.

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

OpenBSD

OpenSSH

unaffected

Version	Status	Constraints
`0`	affected	< 10.3

No data.

No data.

No data.

Project Subscriptions

Vendors	Products
Openbsd Subscribe	Openssh Subscribe

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://marc.info/?l=openssh-unix-dev&m=177513443901484&w=2
https://www.openssh.org/releasenotes.html#10.3p1
https://www.openwall.com/lists/oss-security/2026/04/02/3

History

Thu, 02 Apr 2026 20:30:00 +0000

Type	Values Removed	Values Added
Description		OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing sessions.
First Time appeared		Openbsd Openbsd openssh
Weaknesses		CWE-420
CPEs		cpe:2.3:a:openbsd:openssh::::::::
Vendors & Products		Openbsd Openbsd openssh
References		https://marc.info/?l=openssh-unix-dev&m=177513443901484&w=2 https://www.openssh.org/releasenotes.html#10.3p1 https://www.openwall.com/lists/oss-security/2026/04/02/3
Metrics		cvssV3_1 `{'score': 2.5, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N'}` ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2026-04-02T16:57:31.073Z

Updated: 2026-04-02T18:16:41.820Z

Reserved: 2026-04-02T16:57:30.433Z

Link: CVE-2026-35388

Vulnrichment

Updated: 2026-04-02T17:46:32.744Z

NVD

Status : Received

Published: 2026-04-02T17:16:27.947

Modified: 2026-04-02T17:16:27.947

Link: CVE-2026-35388

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-420

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