SSA-620288

Siemens Security Advisory by Siemens ProductCERT

SSA-620288: Multiple Vulnerabilities (NUCLEUS:13) in CAPITAL VSTAR

Publication Date:	2021-12-14
Last Update:	2022-11-08
Current Version:	V1.1
CVSS v3.1 Base Score:	8.2

SUMMARY

Multiple vulnerabilities (also known as "NUCLEUS:13") have be identified in the Nucleus RTOS (real-time operating system) and reported in the Siemens Security Advisory SSA-044112: https://cert-portal.siemens.com/productcert/pdf/ssa-044112.pdf.

CAPITAL VSTAR uses an affected version of the Nucleus software and inherently contains several of these vulnerabilities.

Siemens recommends specific countermeasures for products where updates are not available.

AFFECTED PRODUCTS AND SOLUTION

Affected Product and Versions	Remediation
Capital VSTAR All versions with enabled Ethernet options	Currently no fix is available See further recommendations from section Workarounds and Mitigations

WORKAROUNDS AND MITIGATIONS

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

CVE-2021-31344, CVE-2021-31345, CVE-2021-31346, CVE-2021-31889, CVE-2021-31890: Apply network segmentation and put the ECUs behind properly configured gateways/firewalls
CVE-2021-31881, CVE-2021-31882, CVE-2021-31883: Disable DHCP client functionality, if feature not used, by deselecting the TcpIpIpV4General/TcpIpDhcpClientEnabled Pre-Compile configuration option

Please follow the General Security Recommendations.

GENERAL SECURITY RECOMMENDATIONS

As a general security measure, Siemens strongly recommends to protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends to configure the environment according to Siemens' operational guidelines for Industrial Security (Download: https://www.siemens.com/cert/operational-guidelines-industrial-security), and to follow the recommendations in the product manuals.

Additional information on Industrial Security by Siemens can be found at: https://www.siemens.com/industrialsecurity

PRODUCT DESCRIPTION

Capital VSTAR is an efficient implementation of the AUTOSAR standard. It is a complete solution including tools and a software platform to meet engineers' needs, from creating ECU extract updates to software platform configurations. Although not based on Nucleus RTOS, VSTAR includes its networking module, Nucleus NET.

VULNERABILITY CLASSIFICATION

The vulnerability classification has been performed by using the CVSS scoring system in version 3.1 (CVSS v3.1) (https://www.first.org/cvss/). The CVSS environmental score is specific to the customer’s environment and will impact the overall CVSS score. The environmental score should therefore be individually defined by the customer to accomplish final scoring.

An additional classification has been performed using the CWE classification, a community-developed list of common software security weaknesses. This serves as a common language and as a baseline for weakness identification, mitigation, and prevention efforts. A detailed list of CWE classes can be found at: https://cwe.mitre.org/.

Vulnerability CVE-2021-31344

ICMP echo packets with fake IP options allow sending ICMP echo reply messages to arbitrary hosts on the network. (FSMD-2021-0004)

CVSS v3.1 Base Score	5.3
CVSS Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C
CWE	CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')

Vulnerability CVE-2021-31345

The total length of an UDP payload (set in the IP header) is unchecked. This may lead to various side effects, including Information Leak and Denial-of-Service conditions, depending on a user-defined applications that runs on top of the UDP protocol. (FSMD-2021-0006)

CVSS v3.1 Base Score	7.5
CVSS Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C
CWE	CWE-1284: Improper Validation of Specified Quantity in Input

Vulnerability CVE-2021-31346

The total length of an ICMP payload (set in the IP header) is unchecked. This may lead to various side effects, including Information Leak and Denial-of-Service conditions, depending on the network buffer organization in memory. (FSMD-2021-0007)

CVSS v3.1 Base Score	8.2
CVSS Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C
CWE	CWE-1284: Improper Validation of Specified Quantity in Input

Vulnerability CVE-2021-31881

When processing a DHCP OFFER message, the DHCP client application does not validate the length of the Vendor option(s), leading to Denial-of-Service conditions. (FSMD-2021-0008)

CVSS v3.1 Base Score	7.1
CVSS Vector	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C
CWE	CWE-125: Out-of-bounds Read

Vulnerability CVE-2021-31882

The DHCP client application does not validate the length of the Domain Name Server IP option(s) (0x06) when processing DHCP ACK packets. This may lead to Denial-of-Service conditions. (FSMD-2021-0011)

CVSS v3.1 Base Score	6.5
CVSS Vector	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C
CWE	CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

Vulnerability CVE-2021-31883

When processing a DHCP ACK message, the DHCP client application does not validate the length of the Vendor option(s), leading to Denial-of-Service conditions. (FSMD-2021-0013)

CVSS v3.1 Base Score	7.1
CVSS Vector	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C
CWE	CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

Vulnerability CVE-2021-31889

Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)

CVSS v3.1 Base Score	7.5
CVSS Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C
CWE	CWE-191: Integer Underflow (Wrap or Wraparound)

Vulnerability CVE-2021-31890

The total length of an TCP payload (set in the IP header) is unchecked. This may lead to various side effects, including Information Leak and Denial-of-Service conditions, depending on the network buffer organization in memory. (FSMD-2021-0017)

CVSS v3.1 Base Score	7.5
CVSS Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C
CWE	CWE-240: Improper Handling of Inconsistent Structural Elements

ADDITIONAL INFORMATION

Products listed in this advisory use Nucleus NET, the networking stack of Nucleus RTOS (Real-time operating system).

For more details regarding the vulnerabilities reported for Nucleus RTOS refer to Siemens Security Advisory SSA-044112: https://cert-portal.siemens.com/productcert/pdf/ssa-044112.pdf

For further inquiries on security vulnerabilities in Siemens products and solutions, please contact the Siemens ProductCERT:

https://www.siemens.com/cert/advisories

HISTORY DATA

V1.0 (2021-12-14):	Publication Date
V1.1 (2022-11-08):	Removed CVE-2021-31884 as Capital VSTAR is not affected

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