Schneider Modicon M580/Quantum Communication Modules Out-of-bounds Write (CVE-2021-29999)

critical Tenable OT Security Plugin ID 504813

Synopsis

The remote OT asset is affected by a vulnerability.

Description

An issue was discovered in Wind River VxWorks through 6.8. There is a possible stack overflow in dhcp server.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

The following text was originally created by the Cybersecurity and Infrastructure Security Agency (CISA). The original can be found at CISA.gov.

Schneider Electric has identified the following specific remediations and mitigations users can apply to reduce risk:

- Modicon M580 communication modules BMENOC BMENOC0321: Version SV1.10 of BMENOC0321 includes a fix for this vulnerability and is available for download.
- Modicon M580 communication modules BMECRA BMECRA31210, Modicon M580/Quantum communication modules BMXCRA BMXCRA31200/BMXCRA31210: Version SV02.80 of BMECRA31210, BMXCRA31200, BMXCRA31210 includes a fix for these vulnerabilities and is available for download.
- 140CRA31200 (Quantum RIO Drop): Version V02.80 of 140CRA31200 includes a fix for these vulnerabilities and is available for download.
- 140CRA31908 (M580 Quantum S908 RIO Drop Adapter): Version V02.80 of 140CRA31908 includes a fix for these vulnerabilities and is available for download.

Schneider Electric strongly recommends the following industry cybersecurity best practices:

- Locate control and safety system networks and remote devices behind firewalls and isolate them from the business network.
- Install physical controls so no unauthorized personnel can access your industrial control and safety systems, components, peripheral equipment, and networks.
- Place all controllers in locked cabinets and never leave them in the "Program" mode.
- Never connect programming software to any network other than the network intended for that device.
- Scan all methods of mobile data exchange with the isolated network such as CDs, USB drives, etc. before use in the terminals or any node connected to these networks.
- Never allow mobile devices that have connected to any other network besides the intended network to connect to the safety or control networks without proper sanitation.
- Minimize network exposure for all control system devices and systems and ensure that they are not accessible from the Internet.
- When remote access is required, use secure methods, such as virtual private networks (VPNs). Recognize that VPNs may have vulnerabilities and should be updated to the most current version available. Also, understand that VPNs are only as secure as the connected devices.

For more information refer to the Schneider Electric Recommended Cybersecurity Best Practices document.

For more information, see Schneider Electric security notification "SEVD-2025-014-03 Wind River VxWorks DHCP server vulnerability"

Additional information about the vulnerability can be found on the Wind River site.

Plugin Details

Severity: Critical

ID: 504813

File Name: tenable_ot_schneider_CVE-2021-29999.nasl

Version: 1.3

Type: remote

Family: Tenable.ot

Published: 11/22/2025

Updated: 3/6/2026

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2021-29999

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:schneider-electric:bmxcra31210_firmware, cpe:/o:schneider-electric:bmxcra31200_firmware, cpe:/o:schneider-electric:bmecra31210_firmware, cpe:/o:schneider-electric:bmenoc0321_firmware, cpe:/o:schneider-electric:140cra31200_firmware, cpe:/o:schneider-electric:140cra31908_firmware

Required KB Items: Tenable.ot/Schneider

Exploit Ease: No known exploits are available

Patch Publication Date: 1/14/2025

Vulnerability Publication Date: 4/13/2021

Reference Information

CVE: CVE-2021-29999

CWE: 787

ICSA: 25-058-01

Detections

Analytics