CVE-2020-35683: Hcc-Embedded Nichestack

High severity, CVSS 7.5. EPSS: 2.3% chance of exploitation in the next 30 days.

An issue was discovered in HCC Nichestack 3.0. The code that parses ICMP packets relies on an unchecked value of the IP payload size (extracted from the IP header) to compute the ICMP checksum. When the IP payload size is set to be smaller than the size of the IP header, the ICMP checksum computation function may read out of bounds, causing a Denial-of-Service.

Affected products

• Hcc-Embedded Nichestack: version 3.0 only
• Siemens 7km9300-0ae02-0aa0 Firmware: before 3.0.4 (fixed in 3.0.4)

Published 2021-08-19. Last modified 2026-06-17.