CVE-2026-84411

critical · 9.3

The web management service in affected RouterOS versions contains an integer underflow in its HTTP request body handling that is reachable before authentication. This can be leveraged by an unauthenticated network attacker to achieve arbitrary code execution as root, or to cause a denial of service, using a single crafted request.

9.3

CVSS

0.9%

EPSS (exploit prob.)

58th

EPSS percentile

2026-10-02

Published

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Weaknesses

CWE-191

References

https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-272-06.json
https://mikrotik.com/download
https://www.cisa.gov/news-events/ics-advisories/icsa-26-272-06

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-84411