CVE-2026-84411

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

02 Oct 2026, 23:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 23:16

Updated : 2026-10-06 15:15

NVD link : CVE-2026-84411

Mitre link : CVE-2026-84411

CVE.ORG link : CVE-2026-84411

JSON object : View

Products Affected

No product.

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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