Answer in brief
CVE-2026-89028 records a High severity (CVSS 8.2) vulnerability in MikroTik RouterOS < 7.24 Heap Corruption via SMB1 SessionSetupAndX. The current sources do not mark it as known exploited. The current feed maps MikroTik/RouterOS (generic), MikroTik/RouterOS (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.2. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps MikroTik/RouterOS (generic), MikroTik/RouterOS (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| MikroTik/RouterOSgeneric | 0 || 7.0.0 | Not reported |
| MikroTik/RouterOSgeneric | >=0 <=6.49.18 || >=7.0.0 <=7.11.2 | Not reported |
Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 1, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 16, 2026
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.
Quoted source text, attributed separately from HOL analysis.