PT-2021-2224 · Silicon · Uc/Tcp-Ip

Amine Amri + 3 · Published 2021-03-04 · Updated 2023-10-13 · CVE-2020-27630

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

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

Name of the Vulnerable Software and Affected Versions Silicon Labs uC/TCP-IP version 3.6.0

Description The issue is related to the improper randomness of TCP Initial Sequence Numbers (ISNs) in the stack protocol used by uC/OS and uC/TCP-IP. This could allow a remote attacker to gain unauthorized access to protected information. The problem stems from the use of insufficiently random values.

Recommendations For Silicon Labs uC/TCP-IP version 3.6.0, consider implementing additional randomness to the TCP ISN generation process as a temporary workaround until a patch is available. Restrict access to sensitive information to minimize the risk of exploitation. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Use of Insufficiently Random Values

Weakness Enumeration

CWE-330

Related Identifiers

BDU:2021-01133

CVE-2020-27630

Affected Products

Uc/Tcp-Ip

References · 10

• https://nvd.nist.gov/vuln/detail/CVE-2020-27630 · Security Note
• https://osv.dev/vulnerability/CVE-2020-27630 · Vendor Advisory
• https://bdu.fstec.ru/vul/2021-01133 · Security Note
• https://cybersecurity-help.cz/vdb/SB2021021012 · Note
• https://cisa.gov/news-events/ics-advisories/icsa-21-042-01 · Note
• https://forescout.com/company/blog/numberjack-forescout-research-labs-finds-nine-isn-generation-vulnerabilities-affecting-tcpip-stacks · Note
• https://forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks · Note
• https://t.me/cvenotify/59185 · Telegram Post
• https://forescout.com · Note
• https://securitylab.ru/news/516461.php · Note