CVE-2026-56719

MikroTik RouterOS before 7.24 contains an out-of-bounds read vulnerability in the userspace SMB daemon that allows unauthenticated attackers to read beyond the end of the request buffer by supplying a crafted uniPwdLen field value in a minimal SMB1 SessionSetupAndX frame. The out-of-bounds read occurs in the SessionSetupAndX handler before any credential validation, potentially exposing sensitive memory contents.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://forum.mikrotik.com/t/7-24-stable-is-released/272381
https://www.vulncheck.com/advisories/mikrotik-routeros-out-of-bounds-read-via-smb1-sessionsetupandx

Configurations

No configuration.

History

16 Sep 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 14:17

Updated : 2026-09-16 16:17

NVD link : CVE-2026-56719

Mitre link : CVE-2026-56719

CVE.ORG link : CVE-2026-56719

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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