Siemens SIMATIC S7-1500 Uncontrolled Resource Consumption (CVE-2019-19281)

high Tenable OT Security Plugin ID 500362

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability has been identified in SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions >= V2.5 and < V20.8), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants) (All versions >= V2.5 and < V2.8), SIMATIC S7-1500 Software Controller (All versions >= V2.5 and < V20.8). Affected devices contain a vulnerability that allows an unauthenticated attacker to trigger a Denial-of-Service condition. The vulnerability can be triggered if specially crafted UDP packets are sent to the device. The security vulnerability could be exploited by an attacker with network access to the affected systems. Successful exploitation requires no system privileges and no user interaction. An attacker could use the vulnerability to compromise the device availability.

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 has released updates for several affected products and recommends specific workarounds and mitigations that customers can apply to reduce the risk:

- Restrict network access to affected devices.
- For SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants), Siemens recommends users update to v20.8 (v2x.8 corresponds to v2.8 of the S7-1500 CPU firmware).

- For SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants), Siemens recommends users update to v2.8
- For SIMATIC S7-1500 Software Controller, Siemens recommends users update to v20.8 (v2x.8 corresponds to v2.8 of the S7-1500 CPU firmware).

For more information on this vulnerability and associated software updates, please see Siemens security advisory SSA-750824

See Also

https://cert-portal.siemens.com/productcert/pdf/ssa-750824.pdf

https://www.us-cert.gov/ics/advisories/icsa-20-042-11

Plugin Details

Severity: High

ID: 500362

Version: 1.6

Type: remote

Family: Tenable.ot

Published: 2/7/2022

Updated: 3/4/2024

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2019-19281

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:siemens:simatic_et_200sp_open_controller_cpu_1515sp_pc2_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1511-1_pn_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1513-1_pn_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1515-2_pn_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1516-3_pn_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1516-3_dp_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1517-3_pn_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1517-3_dp_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1518-4_pn_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1518-4_dp_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1507s_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1508s_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1507s_f_firmware, cpe:/o:siemens:simatic_s7-1500_cpu_1508s_f_firmware

Required KB Items: Tenable.ot/Siemens

Exploit Ease: No known exploits are available

Patch Publication Date: 3/10/2020

Vulnerability Publication Date: 3/10/2020

Reference Information

CVE: CVE-2019-19281

CWE: 400