Docker Sandboxes up to 0.40.x Unix-domain socket relay symlink

Summaryinfo

A vulnerability identified as very critical has been detected in Docker Sandboxes up to 0.40.x. This affects an unknown function of the component Unix-domain socket relay. The manipulation leads to symlink. This vulnerability is traded as CVE-2026-79994. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Docker Sandboxes up to 0.40.x. It has been rated as very critical. This issue affects some unknown functionality of the component Unix-domain socket relay. The manipulation with an unknown input leads to a symlink vulnerability. Using CWE to declare the problem leads to CWE-61. The product, when opening a file or directory, does not sufficiently account for when the file is a symbolic link that resolves to a target outside of the intended control sphere. This could allow an attacker to cause the product to operate on unauthorized files. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The guest-to-host Unix-domain socket relay in Docker Sandboxes validates that a socket path is inside an authorized workspace, but later reconnects using the pathname. A malicious guest can replace an intermediate directory with a symlink between validation and connection, causing the host to connect to an arbitrary AF_UNIX socket outside the shared workspace. This can expose data or host-side capabilities provided by the targeted socket.

It is possible to read the advisory at docs.docker.com. The identification of this vulnerability is CVE-2026-79994 since 08/25/2026. The exploitation is known to be easy. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/15/2026).

Upgrading to version 0.41.0 eliminates this vulnerability.

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Productinfo

Type

• Virtualization Software

Vendor

• Docker

Name

• Sandboxes

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17
• 0.18
• 0.19
• 0.20
• 0.21
• 0.22
• 0.23
• 0.24
• 0.25
• 0.26
• 0.27
• 0.28
• 0.29
• 0.30
• 0.31
• 0.32
• 0.33
• 0.34
• 0.35
• 0.36
• 0.37
• 0.38
• 0.39
• 0.40

CPE 2.3info

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CPE 2.2info

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