An issue was discovered in the IPv6 stack in Contiki through 3.0. There is an insufficient check for the IPv6 header length. This leads to Denial-of-Service and potential Remote Code Execution via a crafted ICMPv6 echo packet.
Conclusion & alert: CVE-2020-25111 is rated High Risk (76.8/100): CVSS Critical severity, with high exploitation likelihood (EPSS 20.07%, 97th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +3.59% over the last day, indicating growing attacker interest. Mandatory action: High exploitation likelihood—assess exposure and prioritize 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 | 16.48% | 20.07% | +3.59% |
| 2 | 2026-03-14 | 11.57% | 16.48% | +4.91% |
| 3 | 2025-11-21 | — | 11.57% | — |
Full EPSS history (18 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.8 | 3.1 | CRITICAL |
|
3.9 | 5.9 | [email protected] |
| 7.5 | 2.0 | HIGH |
|
10.0 | 6.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| contiki-os | contiki-os | <= 3.0 | cpe:2.3:o:contiki-os:contiki-os:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01 | Third Party Advisory US Government Resource |
| https://www.kb.cert.org/vuls/id/815128 | Third Party Advisory US Government Resource |