Rockwell Automation 1794-AENT Flex I/O Series B Buffer Copy Without Checking Size of Input (Classic Buffer Overflow) (CVE-2020-6087)

high Tenable OT Security Plugin ID 500475

Synopsis

The remote OT asset is affected by a vulnerability.

Description

An exploitable denial of service vulnerability exists in the ENIP Request Path Data Segment functionality of Allen- Bradley Flex IO 1794-AENT/B. A specially crafted network request can cause a loss of communications with the device resulting in denial-of-service. An attacker can send a malicious packet to trigger this vulnerability If the ANSI Extended Symbol Segment Sub-Type is supplied, the device treats the byte following as the Data Size in words. When this value represents a size greater than what remains in the packet data, the device enters a fault state where communication with the device is lost and a physical power cycle is required.

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Solution

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

Rockwell Automation recommends affected users ensure they are employing proper network segmentation and security controls when implementing the affected product.

For more information please see the Rockwell Automation Security Advisory (login required).

See Also

https://talosintelligence.com/vulnerability_reports/TALOS-2020-1007

https://www.cisa.gov/news-events/ics-advisories/icsa-20-294-01

http://www.nessus.org/u?6c07952c

Plugin Details

Severity: High

ID: 500475

Version: 1.10

Type: remote

Family: Tenable.ot

Published: 2/7/2022

Updated: 3/4/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.1

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

CVSS Score Source: CVE-2020-6087

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.7

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

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

Vulnerability Information

CPE: cpe:/o:rockwellautomation:flex_i%2fo_1794-aent%2fb_firmware:4.003

Required KB Items: Tenable.ot/Rockwell

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/14/2020

Vulnerability Publication Date: 10/14/2020

Reference Information

CVE: CVE-2020-6087

CWE: 120