# CVE-2025-23018: Security feature bypass in IPv6

> Attackers can spoof and route arbitrary traffic via exposed interfaces due to missing source validation in IPv4-in-IPv6 and IPv6-in-IPv6 tunneling.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Jan 2025
- **Updated:** 3 Nov 2025
- **Also known as:** GHSA-mf23-wm84-g9x3

## What is CVE-2025-23018?

CVE-2025-23018 is a medium-severity vulnerability in IETF IPv6, published on 14 Jan 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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.

Weakness: CWE-940 (Improper Verification of Source of a Communication Channel)

## Which versions are affected by CVE-2025-23018?

It affects 1 product.


Products: Ietf Ipv6.

## How do I fix CVE-2025-23018?

No fix has been published for CVE-2025-23018 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-23018 being exploited?

There is no known exploitation of CVE-2025-23018 in the wild and no public exploit code.

## Other vulnerabilities in IETF IPv6

- [CVE-2016-10142](https://insights.sbomify.com/CVE-2016-10142/): Denial of service in n/a (high 8.6)
- [CVE-2007-2242](https://insights.sbomify.com/CVE-2007-2242/): Denial of service in n/a (high 7.8)
- [CVE-2025-23019](https://insights.sbomify.com/CVE-2025-23019/): Other in IPv6 (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-23018 and fix it if it is affected.

What it is: CVE-2025-23018 is a medium-severity vulnerability in IETF IPv6, published on 14 Jan 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-23018 in the wild and no public exploit code.

Affected product: IETF IPv6. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-23018/ (Markdown: https://insights.sbomify.com/CVE-2025-23018/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-23018
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-23018
- OSV: https://osv.dev/vulnerability/CVE-2025-23018

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-23018/
Summaries are generated and may contain mistakes; the official description above is the record.