CVE-2026-84411SA

Vulnerability Summary

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.

Severity Level

CRITICAL(9.8)

Published Date

Sep 29, 2026

Last Modified

Sep 29, 2026

Exploitation Status

No confirmed exploitation yet

CVE Record Status

Reserved

This CVE ID is referenced in a public advisory, but the CVE Program has not published its official CVE Record yet. Full CVSS/CPE data from NVD will appear here once it does.

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

CWE-191: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics — Score 9.8 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

Affected & Patched Versions

Affected Versions

Not provided by ADMIN for this CVE.

Patched Versions

Not provided by ADMIN for this CVE.

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