CVE-2021-31889: Integer Underflow

Published Nov 9, 2021
·
Updated

A vulnerability has been identified in APOGEE MBC (PPC) (BACnet) (All versions), APOGEE MBC (PPC) (P2 Ethernet) (All versions), APOGEE MEC (PPC) (BACnet) (All versions), APOGEE MEC (PPC) (P2 Ethernet) (All versions), APOGEE PXC Compact (BACnet) (All versions < V3.5.4), APOGEE PXC Compact (P2 Ethernet) (All versions < V2.8.19), APOGEE PXC Modular (BACnet) (All versions < V3.5.4), APOGEE PXC Modular (P2 Ethernet) (All versions < V2.8.19), Capital VSTAR (All versions with enabled Ethernet options), Desigo PXC00-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC00-U (All versions >= V2.3 and < V6.30.016), Desigo PXC001-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC100-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC12-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC128-U (All versions >= V2.3 and < V6.30.016), Desigo PXC200-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC22-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC22.1-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC36.1-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC50-E.D (All versions >= V2.3 and < V6.30.016), Desigo PXC64-U (All versions >= V2.3 and < V6.30.016), Desigo PXM20-E (All versions >= V2.3 and < V6.30.016), Nucleus NET (All versions), Nucleus ReadyStart V3 (All versions < V2017.02.4), Nucleus Source Code (All versions), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions < V0.5.0.0), TALON TC Compact (BACnet) (All versions < V3.5.4), TALON TC Modular (BACnet) (All versions < V3.5.4). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)

Other sources

A vulnerability has been identified in Capital Embedded AR Classic 431-422 (All versions), Capital Embedded AR Classic R20-11 (All versions < V2303), PLUSCONTROL 1st Gen (All versions), SIMOTICS CONNECT 400 (All versions < V0.5.0.0). Malformed TCP packets with a corrupted SACK option leads to Information Leaks and Denial-of-Service conditions. (FSMD-2021-0015)

MITRE

Affected Software

29 affected components
Google Android
Siemens Capital Vstar
Siemens Nucleus NET
Siemens Nucleus ReadyStart v3<2017.02.3
Siemens Nucleus Source Code
All of the following
Siemens Apogee Modular Building Controller Firmware
Siemens Apogee Modular Building Controller
All of the following
Siemens Apogee Modular Equiment Controller Firmware
Siemens Apogee Modular Equiment Controller
All of the following
Siemens Apogee Pxc Compact Firmware
Siemens Apogee Pxc Compact
All of the following
Siemens Apogee Pxc Modular Firmware
Siemens Apogee Pxc Modular
All of the following
Siemens Talon Tc Compact Firmware
Siemens Talon Tc Compact
All of the following
Siemens Talon Tc Modular Firmware
Siemens Talon Tc Modular
Siemens Apogee Modular Building Controller Firmware
Siemens Apogee Modular Building Controller
Siemens Apogee Modular Equiment Controller Firmware
Siemens Apogee Modular Equiment Controller
Siemens Apogee Pxc Compact Firmware
Siemens Apogee Pxc Compact
Siemens Apogee Pxc Modular Firmware
Siemens Apogee Pxc Modular
Siemens Talon Tc Compact Firmware
Siemens Talon Tc Compact
Siemens Talon Tc Modular Firmware
Siemens Talon Tc Modular

Event History

Nov 9, 2021
CVE Published
via MITRE·11:32 AM
Data Sourced
via MITRE·11:32 AM
DescriptionSeverityWeakness
Jan 4, 2022
Data Sourced
via Android·12:00 AM
SeverityAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2021-31889?

The severity of CVE-2021-31889 is critical with a severity value of 9.1.

2

Which software is affected by CVE-2021-31889?

The following Siemens software is affected by CVE-2021-31889: Siemens Capital Vstar, Siemens Nucleus Net, Siemens Nucleus Readystart V3 (up to exclusive version 2017.02.3), Siemens Nucleus Source Code, Siemens Apogee Modular Building Controller Firmware (vulnerable), Siemens Apogee Modular Equiment Controller Firmware (vulnerable), Siemens Apogee Pxc Compact Firmware (up to version V3.5.4), Siemens Apogee Pxc Modular Firmware (vulnerable), Siemens Talon Tc Compact Firmware (vulnerable), Siemens Talon Tc Modular Firmware (vulnerable), and Google Android.

3

How can I fix CVE-2021-31889?

To fix CVE-2021-31889, Siemens recommends following the instructions provided in their product security advisory.

4

Where can I find more information about CVE-2021-31889?

You can find more information about CVE-2021-31889 in the following references: [1](https://cert-portal.siemens.com/productcert/pdf/ssa-044112.pdf), [2](https://cert-portal.siemens.com/productcert/pdf/ssa-114589.pdf), [3](https://cert-portal.siemens.com/productcert/pdf/ssa-223353.pdf).

5

What is the CWE ID of CVE-2021-31889?

The CWE ID of CVE-2021-31889 is 191.

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