CVE-2026-12039
MEDIUM EPSS 1.2%
Published Jun 18, 20262w ago · Modified Jun 22, 20261w ago
5.7 CVSS 4.0
Published Jun 18, 2026 2w ago
Last Modified Jun 22, 2026 1w ago
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
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 Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
1.2% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-923
References 2
- docs.docker.com https://docs.docker.com/ai/sandboxes/
- github.com https://github.com/docker/sbx-releases/releases/tag/v0.33.0
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.