Siemens Multiple Denial of Service in Industrial Products (CVE-2021-44695)

medium Tenable OT Security Plugin ID 500720

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability has been identified in SIMATIC Drive Controller family, SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants), SIMATIC S7-1200 CPU family (incl. SIPLUS variants), SIMATIC S7-1500 CPU 1510SP F-1 PN, SIMATIC S7-1500 CPU 1510SP-1 PN, SIMATIC S7-1500 CPU 1511-1 PN, SIMATIC S7-1500 CPU 1511-1 PN, SIMATIC S7-1500 CPU 1511C-1 PN, SIMATIC S7-1500 CPU 1511C-1 PN, SIMATIC S7-1500 CPU 1511F-1 PN, SIMATIC S7-1500 CPU 1511F-1 PN, SIMATIC S7-1500 CPU 1511T-1 PN, SIMATIC S7-1500 CPU 1511TF-1 PN, SIMATIC S7-1500 CPU 1512C-1 PN, SIMATIC S7-1500 CPU 1512C-1 PN, SIMATIC S7-1500 CPU 1512SP F-1 PN, SIMATIC S7-1500 CPU 1512SP-1 PN, SIMATIC S7-1500 CPU 1513-1 PN, SIMATIC S7-1500 CPU 1513-1 PN, SIMATIC S7-1500 CPU 1513F-1 PN, SIMATIC S7-1500 CPU 1513F-1 PN, SIMATIC S7-1500 CPU 1513R-1 PN, SIMATIC S7-1500 CPU 1515-2 PN, SIMATIC S7-1500 CPU 1515-2 PN, SIMATIC S7-1500 CPU 1515F-2 PN, SIMATIC S7-1500 CPU 1515F-2 PN, SIMATIC S7-1500 CPU 1515R-2 PN, SIMATIC S7-1500 CPU 1515T-2 PN, SIMATIC S7-1500 CPU 1515TF-2 PN, SIMATIC S7-1500 CPU 1516-3 PN/DP, SIMATIC S7-1500 CPU 1516-3 PN/DP, SIMATIC S7-1500 CPU 1516F-3 PN/DP, SIMATIC S7-1500 CPU 1516F-3 PN/DP, SIMATIC S7-1500 CPU 1516T-3 PN/DP, SIMATIC S7-1500 CPU 1516TF-3 PN/DP, SIMATIC S7-1500 CPU 1517-3 PN/DP, SIMATIC S7-1500 CPU 1517F-3 PN/DP, SIMATIC S7-1500 CPU 1517H-3 PN, SIMATIC S7-1500 CPU 1517T-3 PN/DP, SIMATIC S7-1500 CPU 1517TF-3 PN/DP, SIMATIC S7-1500 CPU 1518-4 PN/DP, SIMATIC S7-1500 CPU 1518-4 PN/DP MFP, SIMATIC S7-1500 CPU 1518-4F PN/DP, SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP, SIMATIC S7-1500 CPU 1518HF-4 PN, SIMATIC S7-1500 CPU 1518T-4 PN/DP, SIMATIC S7-1500 CPU 1518TF-4 PN/DP, SIMATIC S7-1500 CPU S7-1518-4 PN/DP ODK, SIMATIC S7-1500 CPU S7-1518F-4 PN/DP ODK, SIMATIC S7-1500 ET 200pro: CPU 1513PRO F-2 PN, SIMATIC S7-1500 ET 200pro: CPU 1513PRO-2 PN, SIMATIC S7-1500 ET 200pro: CPU 1516PRO F-2 PN, SIMATIC S7-1500 ET 200pro: CPU 1516PRO-2 PN, SIMATIC S7-1500 Software Controller, SIMATIC S7-PLCSIM Advanced, SIPLUS ET 200SP CPU 1510SP F-1 PN, SIPLUS ET 200SP CPU 1510SP F-1 PN RAIL, SIPLUS ET 200SP CPU 1510SP-1 PN, SIPLUS ET 200SP CPU 1510SP-1 PN, SIPLUS ET 200SP CPU 1510SP-1 PN RAIL, SIPLUS ET 200SP CPU 1510SP-1 PN RAIL, SIPLUS ET 200SP CPU 1512SP F-1 PN, SIPLUS ET 200SP CPU 1512SP F-1 PN, SIPLUS ET 200SP CPU 1512SP F-1 PN RAIL, SIPLUS ET 200SP CPU 1512SP F-1 PN RAIL, SIPLUS ET 200SP CPU 1512SP-1 PN, SIPLUS ET 200SP CPU 1512SP-1 PN, SIPLUS ET 200SP CPU 1512SP-1 PN RAIL, SIPLUS ET 200SP CPU 1512SP-1 PN RAIL, SIPLUS S7-1500 CPU 1511-1 PN, SIPLUS S7-1500 CPU 1511-1 PN, SIPLUS S7-1500 CPU 1511-1 PN, SIPLUS S7-1500 CPU 1511-1 PN, SIPLUS S7-1500 CPU 1511-1 PN T1 RAIL, SIPLUS S7-1500 CPU 1511-1 PN T1 RAIL, SIPLUS S7-1500 CPU 1511-1 PN TX RAIL, SIPLUS S7-1500 CPU 1511-1 PN TX RAIL, SIPLUS S7-1500 CPU 1511F-1 PN, SIPLUS S7-1500 CPU 1511F-1 PN, SIPLUS S7-1500 CPU 1513-1 PN, SIPLUS S7-1500 CPU 1513-1 PN, SIPLUS S7-1500 CPU 1513-1 PN, SIPLUS S7-1500 CPU 1513-1 PN, SIPLUS S7-1500 CPU 1513F-1 PN, SIPLUS S7-1500 CPU 1513F-1 PN, SIPLUS S7-1500 CPU 1515F-2 PN, SIPLUS S7-1500 CPU 1515F-2 PN, SIPLUS S7-1500 CPU 1515F-2 PN RAIL, SIPLUS S7-1500 CPU 1515F-2 PN T2 RAIL, SIPLUS S7-1500 CPU 1515R-2 PN, SIPLUS S7-1500 CPU 1515R-2 PN TX RAIL, SIPLUS S7-1500 CPU 1516-3 PN/DP, SIPLUS S7-1500 CPU 1516-3 PN/DP, SIPLUS S7-1500 CPU 1516-3 PN/DP, SIPLUS S7-1500 CPU 1516-3 PN/DP, SIPLUS S7-1500 CPU 1516-3 PN/DP RAIL, SIPLUS S7-1500 CPU 1516-3 PN/DP TX RAIL, SIPLUS S7-1500 CPU 1516F-3 PN/DP, SIPLUS S7-1500 CPU 1516F-3 PN/DP, SIPLUS S7-1500 CPU 1516F-3 PN/DP RAIL, SIPLUS S7-1500 CPU 1516F-3 PN/DP RAIL, SIPLUS S7-1500 CPU 1517H-3 PN, SIPLUS S7-1500 CPU 1518-4 PN/DP, SIPLUS S7-1500 CPU 1518-4 PN/DP MFP, SIPLUS S7-1500 CPU 1518F-4 PN/DP, SIPLUS S7-1500 CPU 1518HF-4 PN, SIPLUS TIM 1531 IRC, TIM 1531 IRC. Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an attacker to cause a denial-of- service in the device.

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 released updates for several affected products and recommends updating to the latest versions. Siemens is preparing further updates and recommends countermeasures for products where updates are not, or not yet, available.

- SIMATIC Drive Controller family: Update to V3.0.1 or later version
- SIMATIC S7-PLCSIM Advanced: Update to V5.0 or later version
- SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants): Update to V3.0.1 or later version
- SIMATIC S7-1200 CPU family (incl. SIPLUS variants): Update to V4.6.0 or later version

Siemens has identified the following specific workarounds and mitigations users can apply to reduce risk:

- Restrict access to port 102/TCP to trusted systems with an external firewall

As a general security measure, Siemens strongly 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 to follow the recommendations in the product manuals. Additional information on Industrial Security by Siemens can be found here.

For further inquiries on security vulnerabilities in Siemens products, users should contact Siemens ProductCERT.

For more information, see the associated Siemens security advisory SSA-382653 in HTML and CSAF.

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-382653.pdf

https://www.cisa.gov/news-events/ics-advisories/icsa-22-349-03

Plugin Details

Severity: Medium

ID: 500720

Version: 1.6

Type: remote

Family: Tenable.ot

Published: 1/5/2023

Updated: 2/1/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 6.1

Temporal Score: 4.5

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

CVSS Score Source: CVE-2021-44695

CVSS v3

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 4.3

Vector: CVSS:3.0/AV:N/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:simatic_et_200_sp_open_controller_cpu_1515sp_pc_firmware:-, cpe:/o:siemens:simatic_s7-1200_cpu_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_firmware:2.9.7, cpe:/o:siemens:simatic_s7-1500_cpu_firmware:3.0.1, cpe:/o:siemens:simatic_et200pro_firmware, cpe:/o:siemens:simatic_et200sp_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 12/13/2022

Vulnerability Publication Date: 12/13/2022

Reference Information

CVE: CVE-2021-44695

CWE: 1286