CVE-2026-12539

Docker Sandboxes (sbx) blocks ICMP egress with an authorizer applied only at network-creation time, and does not re-apply it to networks rebuilt from disk when the Docker daemon restarts, so a restart-surviving sandbox forwards ICMP to arbitrary hosts. A workload inside a sandbox, which the threat model treats as untrusted, can therefore defeat the documented ICMP egress block to perform network reconnaissance and exfiltrate data over an ICMP covert channel, regardless of the configured allowlist.

CVSS

No CVSS.

References

Link	Resource
https://docs.docker.com/ai/sandboxes/
https://github.com/docker/sbx-releases/releases/tag/v0.33.0

Configurations

No configuration.

History

26 Oct 2026, 11:10

Type	Values Removed	Values Added
Summary		(es) Docker Sandboxes (sbx) bloquea la salida ICMP con un autorizador aplicado solo en el momento de la creación de la red, y no lo vuelve a aplicar a las redes reconstruidas desde el disco cuando el demonio de Docker se reinicia, por lo que un sandbox que sobrevive a un reinicio reenvía ICMP a hosts arbitrarios. Una carga de trabajo dentro de un sandbox, que el modelo de amenaza trata como no confiable, puede, por lo tanto, eludir el bloqueo de salida ICMP documentado para realizar reconocimiento de red y exfiltrar datos a través de un canal encubierto ICMP, independientemente de la lista de permitidos configurada.

Information

Published : 2026-06-18 14:17

Updated : 2026-10-26 11:10

NVD link : CVE-2026-12539

Mitre link : CVE-2026-12539

CVE.ORG link : CVE-2026-12539

JSON object : View

Products Affected

No product.

CWE

CWE-665

Improper Initialization

CWE-923

Improper Restriction of Communication Channel to Intended Endpoints

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