CVE-2026-12039

Name: CVE-2026-12039
Creator: NVD / NIST
Published: 2026-06-18T14:17:20.78+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.7/10EPSS 0.10%

Last modified Jun 22, 2026

This CVE is reserved or awaiting analysis. Details will appear once published by NVD.

Description

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.

Metrics

CVSS 4.0

5.7/10

CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.10%

1.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-923

References

Timeline

Published: Jun 18, 2026
Last Modified: Jun 22, 2026
Status: Awaiting Analysis

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Source: NVD / NIST