CVE-2020-27213 (GCVE-0-2020-27213)

Vulnerability from cvelistv5 – Published: 2023-10-10 00:00 – Updated: 2024-09-19 15:40
VLAI?
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.
Severity ?
No CVSS data available.
CWE
  • n/a
Assigner
References
Show details on NVD website
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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