# CVE-2013-4125: Denial of service in n/a

> Remote attackers can crash the Linux kernel via crafted IPv6 Router Advertisement messages exploiting a flaw in ECMP route handling.

- **Severity:** Medium 5.4 (`AV:N/AC:H/Au:N/C:N/I:N/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Jul 2013
- **Updated:** 6 Aug 2024
- **Also known as:** CVE-2013-4141, DEBIAN-CVE-2013-4125, GHSA-q98v-4qrj-cxm4

## What is CVE-2013-4125?

CVE-2013-4125 is a medium-severity denial of service vulnerability in Linux kernel, published on 15 Jul 2013. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The fib6_add_rt2node function in net/ipv6/ip6_fib.c in the IPv6 stack in the Linux kernel through 3.10.1 does not properly handle Router Advertisement (RA) messages in certain circumstances involving three routes that initially qualified for membership in an ECMP route set until a change occurred for one of the first two routes, which allows remote attackers to cause a denial of service (system crash) via a crafted sequence of messages.

Weakness: CWE-399

## Which versions are affected by CVE-2013-4125?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2013-4125?

Apply the vendor's patch.

## Is CVE-2013-4125 being exploited?

There is no known exploitation of CVE-2013-4125 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2013-4125 and fix it if it is affected.

What it is: CVE-2013-4125 is a medium-severity denial of service vulnerability in Linux kernel, published on 15 Jul 2013. 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-2013-4125 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2013-4125/ (Markdown: https://insights.sbomify.com/CVE-2013-4125/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2013-4125
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2013-4125
- OSV: https://osv.dev/vulnerability/CVE-2013-4125

---
From sbomify Insights: https://insights.sbomify.com/CVE-2013-4125/
Summaries are generated and may contain mistakes; the official description above is the record.