PT-2021-2229 · Siemens · Simatic Mv400

Published 2021-03-05 · Updated 2023-10-10 · CVE-2020-27632

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

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

Name of the Vulnerable Software and Affected Versions SIMATIC MV400 family versions prior to v7.0.6

Description The issue is related to the implementation of the ISN generator in the TI-NDKTCPIP protocol stack, which uses insufficiently random values. This could allow a remote attacker to predict and hijack TCP sessions, potentially gaining unauthorized access to protected information.

Recommendations For SIMATIC MV400 family versions prior to v7.0.6, update to version v7.0.6 or later to resolve the issue. As a temporary workaround, consider restricting access to the affected system to minimize the risk of exploitation.

Fix

Use of Insufficiently Random Values

Weakness Enumeration

CWE-330

Related Identifiers

BDU:2021-01174

CVE-2020-27632

Affected Products

Simatic Mv400

References · 14

• https://osv.dev/vulnerability/CVE-2020-27632 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2020-27632 · Security Note
• https://cert-portal.siemens.com/productcert/pdf/ssa-599268.pdf · Vendor Advisory
• https://bdu.fstec.ru/vul/2021-01174 · Security Note
• https://cybersecurity-help.cz/vdb/SB2021021015 · Note
• https://cisa.gov/news-events/ics-advisories/icsa-21-042-01 · Note
• https://forescout.com/company/resources/amnesia33-how-tcp-ip-stacks-breed-critical-vulnerabilities-in-iot-ot-and-it-devices · Note
• https://t.me/cibsecurity/24719 · Telegram Post
• https://forescout.com/company/blog/numberjack-forescout-research-labs-finds-nine-isn-generation-vulnerabilities-affecting-tcpip-stacks · Note
• https://t.me/cvenotify/11955 · Telegram Post
• https://forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks · Note
• https://securitylab.ru/vulnerability/516446.php · Note
• https://ti.com/tool/PROCESSOR-SDK-AM437X · Note
• https://securitylab.ru/news/516461.php · Note