An issue was discovered in HCC Embedded NicheStack IPv4 4.1. The dnc_copy_in routine for parsing DNS domain names does not check whether a domain name compression pointer is pointing within the bounds of the packet (e.g., forward compression pointer jumps are allowed), which leads to an Out-of-bounds Read, and a Denial-of-Service as a consequence.
Conclusion & alert: CVE-2020-25767 is rated Moderate Risk (55.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.45%). Core evidence: EPSS rose +1.06% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.39% | 1.45% | +1.06% |
| 2 | 2025-04-06 | 0.31% | 0.39% | +0.08% |
| 3 | 2025-03-17 | — | 0.31% | — |
Full EPSS history (8 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| hcc-embedded | nichestack_ipv4 | 4.1 | cpe:2.3:a:hcc-embedded:nichestack_ipv4:4.1:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://www.forescout.com/blog/new-critical-operational-technology-vulnerabilities-found-on-nichestack/ | Mitigation Third Party Advisory |
| https://www.kb.cert.org/vuls/id/608209 | Third Party Advisory US Government Resource |