CVE-2020-27213
Ethernut Nut/OS TCP ISN Prediction Vulnerability
Description
An issue was discovered in Ethernut Nut/OS 5.1. The code that generates Initial Sequence Numbers (ISNs) for TCP connections derives the ISN from an insufficiently random source. As a result, an attacker may be able to determine the ISN of current and future TCP connections and either hijack existing ones or spoof future ones. While the ISN generator seems to adhere to RFC 793 (where a global 32-bit counter is incremented roughly every 4 microseconds), proper ISN generation should aim to follow at least the specifications outlined in RFC 6528.
INFO
Published Date :
Oct. 10, 2023, 5:15 p.m.
Last Modified :
Oct. 27, 2023, 7:34 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
3.6
Exploitability Score :
3.9
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2020-27213.
| URL | Resource |
|---|---|
| http://lists.egnite.de/mailman/listinfo/en-nut-announce | Not Applicable |
| http://www.ethernut.de/en/download/index.html | Release Notes |
| https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01 | Third Party Advisory US Government Resource |
| https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/ | Exploit Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2020-27213 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2020-27213 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Initial Analysis by [email protected]
Oct. 27, 2023
Action Type Old Value New Value Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Changed Reference Type http://lists.egnite.de/mailman/listinfo/en-nut-announce No Types Assigned http://lists.egnite.de/mailman/listinfo/en-nut-announce Not Applicable Changed Reference Type http://www.ethernut.de/en/download/index.html No Types Assigned http://www.ethernut.de/en/download/index.html Release Notes Changed Reference Type https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01 No Types Assigned https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01 Third Party Advisory, US Government Resource Changed Reference Type https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/ No Types Assigned https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/ Exploit, Third Party Advisory Added CWE NIST CWE-330 Added CPE Configuration OR *cpe:2.3:o:ethernut:nut\/os:5.1:*:*:*:*:*:*:*
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2020-27213 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2020-27213
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.06 }} 0.01%
score
0.26416
percentile