MikroTik RouterOS < 7.24 Out-of-Bounds Read via SMB1 SessionSetupAndX (CVE-2026-56719) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-56719

MikroTik RouterOS < 7.24 Out-of-Bounds Read via SMB1 SessionSetupAndX

Answer in brief

CVE-2026-56719 records a Unknown severity vulnerability in MikroTik RouterOS < 7.24 Out-of-Bounds Read via SMB1 SessionSetupAndX. The current sources do not mark it as known exploited. The current feed maps 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.

Published Sep 16, 2026Updated Sep 16, 2026Source checked Sep 16, 2026First seen by HOL Sep 16, 2026Material review Sep 16, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. 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.

Affected scope and exposure questions

The current feed maps MikroTik/RouterOS (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
MikroTik/RouterOSgeneric	0 \|\| 7.0.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for MikroTik/RouterOS.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 16, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.