CVE-2020-35685 describes a critical vulnerability in HCC Nichestack 3.0 and related Siemens products, where the TCP Initial Sequence Numbers (ISNs) are generated using an insufficiently random source. This flaw allows attackers to predict ISNs, potentially leading to TCP connection hijacking or spoofing. With a CVSS score of 9.1 (CRITICAL), this vulnerability is easily exploitable over the network with low attack complexity, enabling high impact to confidentiality and integrity without user interaction. While there is no known active exploitation or public exploit code (Metasploit, Nuclei, ExploitDB), the vulnerability has garnered some community discussion and media coverage, indicating awareness within the cybersecurity landscape.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
3.0CPE matchmatch criteria | cpe:2.3:a:hcc-embedded:nichestack:3.0:*:*:*:*:*:*:* | ||
< 2.0.0CPE matchmatch criteria | cpe:2.3:o:siemens:sentron_3wa_com190_firmware:*:*:*:*:*:*:*:* | ||
< 1.2.0CPE matchmatch criteria | cpe:2.3:o:siemens:sentron_3wl_com35_firmware:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
Remediation records are not available for this CVE.