Critical Docker Sandbox Vulnerabilities Enable Malicious Guests to Escape Isolated microVM Workspacesnew
Docker patched two sandbox-escape flaws, CVE-2026-77179 and CVE-2026-79994, letting malicious guest workloads access host files and sockets.
Docker fixed CVE-2026-77179 (Critical), a virtio-fs symlink race in Docker Sandboxes 0.28.0 through before 0.42.0 on macOS that could let a guest read or modify arbitrary host files and potentially reach code execution, and CVE-2026-79994 (High), a time-of-check-to-time-of-use flaw in the guest-to-host Unix socket relay affecting 0.37.0 through before 0.42.0. Fixes shipped in Docker Sandboxes 0.42.0, released September 7; Docker recommends clone mode and avoiding read-write host mounts as interim mitigations. The article also references the earlier destination-escape flaw CVE-2026-17106 in docker cp, fixed in Docker Desktop 4.86.0. No exploitation is reported.