OpenBSD OpenSSH up to 10.4 Tunnel Forwarding authorized_keys improper authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$5k-$25k0.79+

Summaryinfo

A vulnerability labeled as very critical has been found in OpenBSD OpenSSH up to 10.4. This impacts an unknown function of the file authorized_keys of the component Tunnel Forwarding. Such manipulation leads to improper authorization. This vulnerability is documented as CVE-2026-73283. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in OpenBSD OpenSSH up to 10.4. Affected by this issue is an unknown part of the file authorized_keys of the component Tunnel Forwarding. The manipulation with an unknown input leads to a improper authorization vulnerability. Using CWE to declare the problem leads to CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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

The advisory is shared for download at openssh.org. This vulnerability is handled as CVE-2026-73283 since 08/11/2026. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 08/11/2026). The MITRE ATT&CK project declares the attack technique as T1548.002.

Upgrading to version 10.5 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: OpenSSH 10.5

Timelineinfo

08/11/2026 Advisory disclosed
08/11/2026 +0 days CVE reserved
08/11/2026 +0 days VulDB entry created
08/11/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: openbsd.org

Advisory: openssh.org
Status: Confirmed

CVE: CVE-2026-73283 (🔒)
GCVE (CVE): GCVE-0-2026-73283
GCVE (VulDB): GCVE-100-388496

Entryinfo

Created: 08/11/2026 21:47
Changes: 08/11/2026 21:47 (56)
Complete: 🔍
Cache ID: 216::103

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