PT-2019-3833 · Schneider Electric · Modicon Bmxcra+3

Published 2019-10-08 · Updated 2022-02-03 · CVE-2019-6847

Positive Technologies (AI Summary)

CVSS v2.0

6.8

Medium

Base vector

AV:N/AC:L/Au:S/C:N/I:N/A:C

Name of the Vulnerable Software and Affected Versions Modicon M580 (all firmware versions) Modicon M340 (all firmware versions) Modicon BMxCRA (all firmware versions) 140CRA (all firmware versions)

Description A vulnerability exists in the Modicon controllers' firmware, related to the improper handling of exceptional conditions. This issue is associated with the lack of version checking for firmware updates. When upgrading the firmware using the FTP protocol with a version incompatible with the application in the controller, it could cause a Denial of Service attack on the FTP service. The vulnerability can be exploited remotely, allowing an attacker to upload an incompatible firmware version, resulting in a denial of service.

Recommendations For Modicon M580, consider disabling the FTP service until a compatible firmware version is available. For Modicon M340, restrict access to the FTP protocol to minimize the risk of exploitation. For Modicon BMxCRA and 140CRA, avoid using the FTP protocol for firmware updates until a patch is available. As a temporary workaround, consider implementing additional security measures to restrict remote access to the controllers.

Fix

Improper Handling of Exceptional Conditions

Weakness Enumeration

CWE-248

CWE-755

Related Identifiers

BDU:2019-04192

CVE-2019-6847

Affected Products

140Cra

Modicon Bmxcra

Modicon M340

Modicon M580

References · 5

• https://bdu.fstec.ru/vul/2019-04192 · Security Note
• https://se.com/ww/en/download/document/SEVD-2019-281-02 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2019-6847 · Security Note
• https://schneider-electric.com/en/download/document/SEVD-2019-281-02 · Note
• https://t.me/cvenotify/13434 · Telegram Post