CVE-2026-12039

Docker Sandboxes (sbx) enforces an HTTP/S-only egress allowlist but does not apply it to DNS resolution: the per-network embedded DNS server forwards any queried name to the host resolver whenever the network is internet-connected, without consulting the policy. A workload inside a sandbox, which the threat model treats as untrusted, can therefore encode data into DNS labels for an attacker-controlled domain and exfiltrate it through a DNS covert channel, bypassing 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

18 Jun 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-18 14:17

Updated : 2026-06-30 18:16

NVD link : CVE-2026-12039

Mitre link : CVE-2026-12039

CVE.ORG link : CVE-2026-12039

JSON object : View

Products Affected

No product.

CWE

CWE-923

Improper Restriction of Communication Channel to Intended Endpoints

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