CVE-2026-39042

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

An issue in MikroTIk (SIA Mikrotikls, Latvia) RouterOS 7.21.x before v.7.21.4 and 7.22.x before v.7.22.2 allows a remote attacker to cause a denial of service via the unflatten() function in libumsg.so.

Published 2026-07-13. Last modified 2026-07-15.