5.7

CVE-2026-12039: docker docker sandboxes

CVSS: 5.7v4.0MediumAwaiting analysis
Published 18-06-2026Last modified 13-08-2026
Open JSON

Vulnerability summary

CVE-2026-12039 is a medium (CVSS 5.7) vulnerability in docker docker sandboxes. EPSS estimates a 0.10% chance of exploitation in the next 30 days, higher than 0.9% of scored vulnerabilities.

Overall risk
23/100
0100
Low · default modelHow is this calculated?
CVSS score
5.7/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.10%
0%100%
Low · -0.04 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 18-06-2026
    PublishedVulnerability first disclosed.
  2. 13-08-2026
    Last modifiedVulnerability information updated.

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 metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.10%

Chance of exploitation in the next 30 days

Percentile

1%

Versus all other CVEs

30-day change

-0.04 pp

From 0.15% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.10%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Docker1 product

1 vendor · 1 product

References

2 links