IPv4-in-IPv6 and IPv6-in-IPv6 tunneling (RFC 2473) do not require the validation or verification of the source of a network packet, allowing an attacker to spoof and route arbitrary traffic via an exposed network interface. This is a similar issue to CVE-2020-10136.
Conclusion & alert: CVE-2025-23018 is rated Low Risk (31.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.10%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
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 | 2025-11-21 | 0.18% | 0.10% | -0.08% |
| 2 | 2025-11-18 | 0.05% | 0.18% | +0.13% |
| 3 | 2025-08-20 | — | 0.05% | — |
Full EPSS history (8 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.4 | 3.1 | MEDIUM |
|
2.2 | 2.7 | [email protected] |
| 6.5 | 3.1 | MEDIUM |
|
2.2 | 3.7 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
redhat
|
low | — | https://access.redhat.com/security/cve/CVE-2025-23018 |
| URL | Tags |
|---|---|
| https://datatracker.ietf.org/doc/html/rfc2473 | Technical Description |
| https://papers.mathyvanhoef.com/usenix2025-tunnels.pdf | Technical Description |
| https://www.top10vpn.com/research/tunneling-protocol-vulnerability/ | Technical Description |
| https://www.kb.cert.org/vuls/id/199397 |