CVE intelligence and bounded remediation

CVE-2020-35684 — An issue was discovered in HCC Nichestack 3.0

High CVSS 7.5

An issue was discovered in HCC Nichestack 3.0. The code that parses TCP packets relies on an unchecked value of the IP payload size (extracted from the IP header) to compute the length of the TCP payload within the TCP checksum computation function. When the IP payload size is set to be smaller than the size of the IP header, the TCP checksum computation function may read out of bounds (a low-impact write-out-of-bounds is also possible).

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 / 3.0
siemens / sentron_3wl_com35_firmware
siemens / sentron_3wa_com190_firmware

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

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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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