CVE-2026-73283

Awaiting Analysis Awaiting Analysis - Queue

OpenSSH restrict Keyword Tunnel Forwarding Bypass

Publication date: 2026-08-11

Last updated on: 2026-08-31

Assigner: MITRE

Description

In sshd in OpenSSH before 10.5, the restrict keyword (in authorized_keys) was supposed to be applicable to tunnel forwarding but was not.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-08-11

Last Modified

2026-08-31

Generated

2026-09-01

AI Q&A

2026-08-12

EPSS Evaluated

2026-08-30

NVD

CVE-2026-73283

EUVD

EUVD-2026-56892

Affected Vendors & Products

Vendor	Product	Version / Range
openssh	openssh	to 10.5 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-670	The code contains a control flow path that does not reflect the algorithm that the path is intended to implement, leading to incorrect behavior any time this path is navigated.

Attack-Flow Graph

Executive Summary

This vulnerability in OpenSSH before version 10.5 involves the restrict keyword in authorized_keys not being properly enforced for tunnel forwarding. The restrict keyword is meant to limit what a key can do, but due to this flaw, it fails to restrict tunnel forwarding as intended.

Detection Guidance

This vulnerability can be detected by checking the OpenSSH version on your system. If you are running a version before 10.5, you are likely affected. Use the command 'sshd -V' or 'ssh -V' to check the version.

Impact Analysis

An attacker with access to a restricted key could potentially use it to set up unauthorized tunnel forwarding, bypassing intended access controls. This could lead to data exfiltration or unauthorized network access, depending on the system configuration.

Compliance Impact

This vulnerability may impact compliance by allowing unauthorized network access or data transfers, which could violate data protection requirements in GDPR or HIPAA. Organizations must ensure proper access controls to maintain compliance.

Mitigation Strategies

Upgrade OpenSSH to version 10.5 or later to address the issue with the restrict keyword in authorized_keys not applying to tunnel forwarding.

Hi! I’m here to help you understand CVE-2026-73283. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70