CVE-2026-89028

MikroTik RouterOS < 7.24 Heap Corruption via SMB1 SessionSetupAndX

Published: Sep 16, 2026Updated: Sep 17, 2026 Sources: CVE List NVDCWE-122

7.5HIGH

Description

MikroTik RouterOS before 7.24 contains a heap memory corruption vulnerability in the userspace SMB daemon that allows remote attackers to corrupt adjacent heap memory by supplying a crafted uniPwdLen value in the SMB1 SessionSetupAndX handler. An attacker can send a malformed SMB1 request with a uniPwdLen field that triggers an integer underflow, causing the resulting value to be used as the copy length in a memory copy operation into a smaller heap buffer, corrupting adjacent heap memory.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-122 CWE-191

Affected Products

MikroTik

commercial·LVaka routeros, winbox

RouterOSOn-premNetwork Device

Networking Infrastructure / router-switch

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

Privilege Escalation

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References

https://forum.mikrotik.com/t/7-24-stable-is-released/272381

forum.mikrotik.com

https://www.vulncheck.com/advisories/mikrotik-routeros-heap-corruption-via-smb1-sessionsetupandx

vulncheck.com

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