{"id":"CVE-2026-12039","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-12039","generatedAt":"2026-10-28T03:24:14.034Z","title":"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…","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.","published":"2026-06-18T14:17:21.000Z","lastModified":"2026-10-26T11:10:00.000Z","status":"Awaiting Analysis","sourceIdentifier":"security@docker.com","cvss":{"version":"4.0","score":5.7,"severity":"MEDIUM","vector":"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/M"},"cwe":["CWE-923"],"affected":[],"epss":{"score":0.00103,"percentile":0.00985,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.10%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://docs.docker.com/ai/sandboxes/","source":"security@docker.com"},{"url":"https://github.com/docker/sbx-releases/releases/tag/v0.33.0","source":"security@docker.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-12039","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}