---
title: "CVE-2026-101039: FAST FAC1900R - Buffer Overflow"
description: "FAST FAC1900R 20190827_2.0.2 contains a stack-based buffer overflow caused by manipulation in copy_msg_element function of devdiscover Service, letting remote attackers execute code, exploit requires crafted input."
url: https://panop.io/threat-heartbeat/CVE-2026-101039/
---

# CVE-2026-101039 FAST FAC1900R - Buffer Overflow

FAST FAC1900R 20190827\_2.0.2 contains a stack-based buffer overflow caused by manipulation in copy\_msg\_element function of devdiscover Service, letting remote attackers execute code, exploit requires crafted input.

CVSS base score 10.0 /10

Critical

CISA KEV

Not listed

Public exploit

None known

Authentication

Not required

EPSS

0.74% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-101039)

## Details

Type

Buffer Overflow

Impact

Remote Code Execution

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Published

28 September 2026

Updated

15 October 2026

Weakness

[CWE-119](https://cwe.mitre.org/data/definitions/119.html)

## Vendor fix

Update to the latest version or apply vendor patches when available.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-101039](https://nvd.nist.gov/vuln/detail/CVE-2026-101039)
- [https://vuldb.com/submit/927251](https://vuldb.com/submit/927251)
- [https://vuldb.com/vuln/410907](https://vuldb.com/vuln/410907)
- [https://vuldb.com/vuln/410907/cti](https://vuldb.com/vuln/410907/cti)
- [https://github.com/xiaobor123/vuls-find-VxWorks/tree/main/vul-find-FAST\_FAC1900R-copy\_msg\_element(2)](https://github.com/xiaobor123/vuls-find-VxWorks/tree/main/vul-find-FAST_FAC1900R-copy_msg_element%282%29)
- [https://vuldb.com/cve/CVE-2026-101039](https://vuldb.com/cve/CVE-2026-101039)

[← All CVEs](https://panop.io/threat-heartbeat/)

## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

[Book a demo](https://panop.io/demo)