Description
An issue in MikroTIk (SIA Mikrotikls, Latvia) RouterOS 7.21.x before v.7.21.4 and 7.22.x before v.7.22.2 allows a remote attacker to cause a denial of service via the unflatten() function in libumsg.so.
Published: 2026-07-13
Score: 7.5 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

No advisories yet.

History

Sat, 25 Jul 2026 18:15:00 +0000

Type Values Removed Values Added
Title Integer Overflow in RouterOS IPC Unflatten Function Causes Remote DoS

Fri, 24 Jul 2026 08:15:00 +0000

Type Values Removed Values Added
Title Integer Overflow in RouterOS IPC Unflatten Function Causes Remote DoS

Mon, 20 Jul 2026 23:45:00 +0000

Type Values Removed Values Added
Title Integer Overflow in MikroTik RouterOS unflatten() Function Causes Remote Denial of Service

Thu, 16 Jul 2026 10:00:00 +0000

Type Values Removed Values Added
Title Integer Overflow in MikroTik RouterOS unflatten() Function Causes Remote Denial of Service

Tue, 14 Jul 2026 17:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-190
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

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


Mon, 13 Jul 2026 23:45:00 +0000

Type Values Removed Values Added
First Time appeared Mikrotik
Mikrotik routeros
Vendors & Products Mikrotik
Mikrotik routeros

Mon, 13 Jul 2026 22:15:00 +0000

Type Values Removed Values Added
Description An issue in MikroTIk (SIA Mikrotikls, Latvia) RouterOS 7.21.x before v.7.21.4 and 7.22.x before v.7.22.2 allows a remote attacker to cause a denial of service via the unflatten() function in libumsg.so.
References

Subscriptions

Mikrotik Routeros
cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-07-14T16:27:12.476Z

Reserved: 2026-04-06T00:00:00.000Z

Link: CVE-2026-39042

cve-icon Vulnrichment

Updated: 2026-07-14T16:25:02.357Z

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-25T18:00:06Z

Weaknesses