CVE-2026-84411

MikroTik RouterOS Integer Underflow

Published Oct 2, 2026 CVSS 4.0 · 9.3 Critical EPSS < 1% KEV · Not listed
Description
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.

Remediation

Vendor Solution

MikroTik recommends users update RouterOS to version 7.24 or later. The upgrade can be downloaded from the MikroTik website. https://mikrotik.com/download

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Mikrotik
Mikrotik routeros
Vendors & Products Mikrotik
Mikrotik routeros
Type Values Removed Values Added
Description 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.
Title MikroTik RouterOS Integer Underflow
Weaknesses CWE-191
References
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 9.3, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
icscert
Published
Updated
Oct 3, 2026, 3:52 PM
Reserved
Sep 1, 2026, 5:04 PM
Status
Awaiting Analysis
Published
Oct 2, 2026, 11:16 PM
Modified
Oct 6, 2026, 3:15 PM