CVE-2020-35684

HIGH

HCC Nichestack 3.0 - Out-of-Bounds Read and Write via TCP Checksum Computation

Title source: llm
STIX 2.1

Description

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).

References (4)

Core 4
Core References
Product x_refsource_misc
https://www.hcc-embedded.com
Mitigation, Third Party Advisory x_refsource_confirm
https://cert-portal.siemens.com/productcert/pdf/ssa-789208.pdf
Third Party Advisory, US Government Resource third-party-advisory x_refsource_cert-vn
https://www.kb.cert.org/vuls/id/608209

Scores

CVSS v3 7.5
EPSS 0.0070
EPSS Percentile 72.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-20
Status published
Products (3)
hcc-embedded/nichestack 3.0
siemens/sentron_3wa_com190_firmware < 2.0.0
siemens/sentron_3wl_com35_firmware < 1.2.0
Published Aug 19, 2021
Tracked Since Feb 18, 2026