CVE-2026-84411 json
MikroTik RouterOS Integer Underflow
published 2026-10-02 37 d ago modified 2026-10-06 33 d ago also EUVD-2026-91836
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 58%
- public exploits
- 0
- none known
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.
Patch / fix
- MikroTik RouterOS 7.24
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
cisa ICSA-26-272-06 updated cvss 9.8
MikroTik RouterOS
-
MikroTik RouterOS <7.24affected: fixed in 7.24 mikrotik.com
From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 36 d ago
Exploit prediction
0.86% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 9.3 | 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 |
| CNA | 4.0 | 9.3 | 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 |
Affected products
- MikroTik RouterOS
Classification
- Weakness
-
- CWE-191 Integer Underflow (Wrap or Wraparound)
References
Sources
- CVE List CVE-2026-84411
- NVD CVE-2026-84411
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