CVE-2026-89028
MikroTik · published 2026-09-16
Source record Collected from the National Vulnerability Database (NVD)
Description
Description by VulnCheck via the CVE Program.
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.
Filed by VulnCheck; not a statement by MikroTik.
Status at the source
- NVD status: Awaiting Analysis — NVD has not analysed this CVE.
Affected products, as the source lists them
| Vendor | Product | Versions |
|---|---|---|
| MikroTik | RouterOS | 0 – 6.49.18 and earlier: affected 7.0.0 – 7.11.2 and earlier: affected 7.24.0: unaffected |
DeSpy has not checked any unit, hardware revision or firmware. A product missing here is not a statement that it is unaffected.
Scores, as their sources published them
- CVSS 4.0: 8.2 HIGH — as published by VulnCheck (Secondary)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/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 - CVSS 3.1: 7.5 HIGH — as published by VulnCheck (Secondary)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - SSVC — CISA's assessment (SSVC 2.0.3, CISA Coordinator): Exploitation: none · Automatable: no · Technical impact: partial
DeSpy does not score records. These are the sources' own values.
Weaknesses
Sources
References the source lists
- https://forum.mikrotik.com/t/7-24-stable-is-released/272381
- https://www.vulncheck.com/advisories/mikrotik-routeros-heap-corruption-via-smb1-sessionsetupandx
Source dates: published 2026-09-16, last changed 2026-09-24. DeSpy's copy of this version is dated 2026-09-28.
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