cve-2020-27213
Vulnerability from cvelistv5
Published
2023-10-10 00:00
Modified
2024-09-19 15:40
Severity
Summary
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.
References
SourceURLTags
cve@mitre.orghttp://lists.egnite.de/mailman/listinfo/en-nut-announceNot Applicable
cve@mitre.orghttp://www.ethernut.de/en/download/index.htmlRelease Notes
cve@mitre.orghttps://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01Third Party Advisory, US Government Resource
cve@mitre.orghttps://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/Exploit, Third Party Advisory
Impacted products
VendorProduct
n/an/a
Show details on NVD website

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