CVE-2026-89021: MikroTik RouterOS

Medium severity, CVSS 6.9. EPSS: 0.4% chance of exploitation in the next 30 days.

MikroTik RouterOS before 7.24.2 contains a path traversal vulnerability in the container package OCI/tar image extraction that allows attackers to write files outside the container root by supplying a crafted container image with symlinks pointing to arbitrary paths. Attackers can exploit unsanitized tar member path extraction during container import via /container/add to achieve root-privileged file creation, directory creation, file deletion via overlayfs whiteout, and hardlink creation on the persistent data partition without ever starting the container. The 7.23.x long-term branch does not contain this fix; the container binaries in container-7.23.3.npk and container-7.23.4.npk are byte-identical. The vendor has confirmed that the issue is not resolved in the long-term release and that the fix is carried forward only in the stable branch from 7.24.2 onward, with no backport to the long-term branch planned.

Affected products

• MikroTik RouterOS: before 7.24.2 (fixed in 7.24.2)

Published 2026-09-14. Last modified 2026-09-24.