CVE-2021-31401

An issue was discovered in tcp_rcv() in nptcp.c in HCC embedded InterNiche 4.0.1. The TCP header processing code doesn't sanitize the value of the IP total length field (header length + data length). With a crafted IP packet, an integer overflow occurs whenever the value of the IP data length is calculated by subtracting the length of the header from the total length of the IP packet.

• CWE-20

• https://cert-portal.siemens.com/productcert/pdf/ssa-789208.pdfMitigation, Third Party Advisory
• https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/Mitigation, Third Party Advisory
• https://www.kb.cert.org/vuls/id/608209Third Party Advisory, US Government Resource
• https://cert-portal.siemens.com/productcert/pdf/ssa-789208.pdfMitigation, Third Party Advisory
• https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/Mitigation, Third Party Advisory
• https://www.kb.cert.org/vuls/id/608209Third Party Advisory, US Government Resource

Published

Aug 19, 2021

Last Modified

Jun 17, 2026

Status

Modified

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