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  1. CVEs
  2. CVE-2020-27632
  1. CVEs

CVE-2020-27632

high
  • Information
  • CPEs
  • Plugins

Description

In SIMATIC MV400 family versions prior to v7.0.6, the ISN generator is initialized with a constant value and has constant increments. An attacker could predict and hijack TCP sessions.

References

  • References
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https://www.tenable.com/cyber-exposure/2021-threat-landscape-retrospective

https://www.tenable.com/blog/numberjack-nine-vulnerabilities-across-multiple-open-source-tcpip-stacks

https://www.forescout.com/resources/numberjack-weak-isn-generation-in-embedded-tcpip-stacks/

https://www.cisa.gov/news-events/ics-advisories/icsa-21-042-01

https://cert-portal.siemens.com/productcert/pdf/ssa-599268.pdf

Details

Source: Mitre, NVD

Published: 2021-03-10

Updated: 2023-10-10

Named Vulnerability: NUMBER:JACK

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Severity: High

EPSS

EPSS: 0.00379

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