CVE intelligence and bounded remediation
CVE-2021-31401 — An issue was discovered in tcp_rcv() in nptcp.c in HCC embedded InterNiche 4.0.1
High
CVSS 7.5
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.
- Severity
- High
- CVSS
- 7.5 (3.1)
- Published
- 2021-08-19
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-20
Affected products
- hcc-embedded / nichestack
- siemens / sentron_3wl_com35_firmware
- siemens / sentron_3wa_com190_firmware
Matched remediation archetype
Buffer bounds, memory safety, and memory corruption
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
- Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
- Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.
Remediate safely
- Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
- Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
- Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.
Authoritative sources
Complete CVE record and remediation plan
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