CVE-2026-84411: CWE-191 in MikroTik RouterOS
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.
CVSS v3.1
Score 9.8critical
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The web management service in certain RouterOS versions contains an integer underflow vulnerability in its HTTP request body processing that is exploitable prior to authentication. An unauthenticated network attacker can leverage this flaw to achieve arbitrary code execution with root privileges or trigger a denial of service condition by sending a specially crafted HTTP request. The vulnerability is identified as CWE-191 and has a CVSS v3.1 base score of 9.8, indicating critical severity.
Potential Impact
Successful exploitation allows an unauthenticated attacker to execute arbitrary code as root or cause a denial of service on the affected RouterOS device. This compromises device integrity, confidentiality, and availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-xj4h-hf2x-2q43
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-84411"]
- Database Specific Severity
- CRITICAL
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ac1399fa43b0b3b89d69a86
Added to database: 10/03/2026, 17:21:35 UTC
Last enriched: 10/03/2026, 17:36:45 UTC
Last updated: 10/10/2026, 06:48:19 UTC
Views: 30
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.