CVE-2026-39042

highCVSS 7.5covered by 1 sourcefirst seen 2026-07-13

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.

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Exploitation outlook

Low exploitation risk0.41% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 34% of all EPSS-scored CVEs.

Advisory coverage (1)

highCVE-2026-39042: An issue in MikroTIk (SIA Mikrotikls, Latvia) RouterOS 7.21.x before v.7.21.4 and 7.22.x befor…nvd · 2026-07-13

External references

NVD record for CVE-2026-39042

CVE.org record

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