{"id":64166,"date":"2026-06-19T08:28:40","date_gmt":"2026-06-19T08:28:40","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=64166"},"modified":"2026-06-19T08:28:40","modified_gmt":"2026-06-19T08:28:40","slug":"docker-sandboxes-icmp-egress-restriction-bypass-after-daemon-restart","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=64166","title":{"rendered":"Docker Sandboxes ICMP egress restriction bypass after daemon restart_CVE-2026-12539"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Docker Sandboxes (sbx) blocks ICMP egress with an authorizer applied only at network-creation time, and does not re-apply it to networks rebuilt from disk when the Docker daemon restarts, so a restart-surviving sandbox forwards ICMP to arbitrary hosts. 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