Siemens SCALANCE LPE9403 Improper Initialization (CVE-2021-20317)

medium Tenable OT Security Plugin ID 501881

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.

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.

Siemens recommends users of the affected product update to Version 2.0 or later.

As a general security measure, Siemens recommends protecting network access to devices with appropriate mechanisms. To operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemens’ operational guidelines for industrial security and following recommendations in the product manuals.

Additional information on industrial security by Siemens can be found on the Siemens industrial security webpage.

For more information see Siemens Security Advisory SSA-222547

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf

https://www.cisa.gov/news-events/ics-advisories/icsa-22-167-09

https://cwe.mitre.org/data/definitions/665.html

Plugin Details

Severity: Medium

ID: 501881

Version: 1.3

Type: remote

Family: Tenable.ot

Published: 1/15/2024

Updated: 9/4/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 3.6

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

CVSS Score Source: CVE-2021-20317

CVSS v3

Risk Factor: Medium

Base Score: 4.4

Temporal Score: 3.9

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

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

Vulnerability Information

CPE: cpe:/o:siemens:scalance_lpe9403_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 6/14/2022

Vulnerability Publication Date: 9/27/2021

Reference Information

CVE: CVE-2021-20317

ICSA: 22-167-09