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TI-2026-10377 Aliases CVE-2026-12039GHSA-4crj-qc6g-g3xj

Docker Sandboxes network egress allowlist bypass via unfiltered DNS resolution

Priority LOW 24CWE-923Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00103 0th percentileScored 2026-11-07
Fix Fixed Docker Sandboxes (Docker): 0.33.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
DockerDocker Sandboxes0.13.0 to before 0.33.00.33.0Patch availableCNA
  • Docker Sandboxes VendorDocker Affected 0.13.0 to before 0.33.0 Fixed in 0.33.0 Patch available CNA

CPE names CNA · 1

CPEVersionsRoleVendor
cpe:2.3:a:docker:docker_sandboxes:*:*:*:*:*:*:*:*——Docker
  • cpe:2.3:a:docker:docker_sandboxes:*:*:*:*:*:*:*:* Versions — — ·Docker

Remediation

  • Fix · CNA Docker Sandboxes (Docker) Fixed in 0.33.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Docker Sandboxes 0.33.0

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-10757 Docker Sandboxes ICMP egress restriction bypass after daemon restartPriority LOW 22
    Show all 2 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-12039
  2. 2026-10-03 Alias added: GHSA-4crj-qc6g-g3xj

References

Other 2

  • TI-2019-11833 Docker Desktop Community Edition before 2.1.0.1 allows local users to gain privileges by… KEVCVSS 3.1HIGH 7.8
  • TI-2019-04061 runc through 1.0-rc6, as used in Docker before 18.09.2 and other products, allows… CVSS 3.1HIGH 8.6
  • TI-2025-08316 Docker Desktop allows unauthenticated access to Docker Engine API from containers CVSS 4.0CRITICAL 9.3
  • TI-2025-02823 Elevation of Privilege in Docker Desktop for Windows during Upgrade due to Insecure Directory Deletion CVSS 4.0HIGH 7.3
  • TI-2026-14229 Tar extraction in moby/go-archive can write outside the destination directory via link following CVSS 4.0HIGH 7.1
  • TI-2023-21271 Docker Machine through 0.16.2 allows an attacker, who has control of a worker node, to… CVSS 3.1MEDIUM 6.5
See all 132 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences