# CVE-2012-4423: Null dereference in n/a

> Remote attackers can cause a denial of service in libvirt via crafted RPC calls triggering a NULL pointer dereference.

- **Severity:** Medium 5.0 (`AV:N/AC:L/Au:N/C:N/I:N/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Nov 2012
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2012-4423, GHSA-82q7-xh57-cm62, RHSA-2012:1359

## What is CVE-2012-4423?

CVE-2012-4423 is a medium-severity vulnerability in Redhat Libvirt, published on 19 Nov 2012. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The virNetServerProgramDispatchCall function in libvirt before 0.10.2 allows remote attackers to cause a denial of service (NULL pointer dereference and segmentation fault) via an RPC call with (1) an event as the RPC number or (2) an RPC number whose value is in a "gap" in the RPC dispatch table.

## Which versions are affected by CVE-2012-4423?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `libvirt` | Red Hat:enterprise_linux:6::client | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-client` | Red Hat:enterprise_linux:6::client | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-debuginfo` | Red Hat:enterprise_linux:6::client | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-devel` | Red Hat:enterprise_linux:6::client | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-lock-sanlock` | Red Hat:enterprise_linux:6::client | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-python` | Red Hat:enterprise_linux:6::client | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt` | Red Hat:enterprise_linux:6::computenode | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-client` | Red Hat:enterprise_linux:6::computenode | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-debuginfo` | Red Hat:enterprise_linux:6::computenode | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-devel` | Red Hat:enterprise_linux:6::computenode | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-lock-sanlock` | Red Hat:enterprise_linux:6::computenode | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-python` | Red Hat:enterprise_linux:6::computenode | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt` | Red Hat:enterprise_linux:6::server | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-client` | Red Hat:enterprise_linux:6::server | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-debuginfo` | Red Hat:enterprise_linux:6::server | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-devel` | Red Hat:enterprise_linux:6::server | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-lock-sanlock` | Red Hat:enterprise_linux:6::server | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-python` | Red Hat:enterprise_linux:6::server | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt` | Red Hat:enterprise_linux:6::workstation | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-client` | Red Hat:enterprise_linux:6::workstation | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-debuginfo` | Red Hat:enterprise_linux:6::workstation | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-devel` | Red Hat:enterprise_linux:6::workstation | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-lock-sanlock` | Red Hat:enterprise_linux:6::workstation | All versions | 0:0.9.10-21.el6_3.5 |
| `libvirt-python` | Red Hat:enterprise_linux:6::workstation | All versions | 0:0.9.10-21.el6_3.5 |

Products: Redhat Libvirt.

## How do I fix CVE-2012-4423?

Upgrade to a fixed version.

## Is CVE-2012-4423 being exploited?

There is no known exploitation of CVE-2012-4423 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Libvirt

- [CVE-2013-4401](https://insights.sbomify.com/CVE-2013-4401/): Missing authorization in n/a (high 8.5)
- [CVE-2017-2635](https://insights.sbomify.com/CVE-2017-2635/): Null dereference in libvirt (high 7.7)
- [CVE-2013-4400](https://insights.sbomify.com/CVE-2013-4400/): Privilege escalation in n/a (high 7.2)
- [CVE-2013-4291](https://insights.sbomify.com/CVE-2013-4291/): Privilege escalation in n/a (medium 6.9)
- [CVE-2011-1146](https://insights.sbomify.com/CVE-2011-1146/): Missing authorization in n/a (medium 6.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2012-4423 and fix it if it is affected.

What it is: CVE-2012-4423 is a medium-severity vulnerability in Redhat Libvirt, published on 19 Nov 2012. 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-2012-4423 in the wild and no public exploit code.

Affected product: Redhat Libvirt. 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-2012-4423/ (Markdown: https://insights.sbomify.com/CVE-2012-4423/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2012-4423
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2012-4423
- OSV: https://osv.dev/vulnerability/CVE-2012-4423

---
From sbomify Insights: https://insights.sbomify.com/CVE-2012-4423/
Summaries are generated and may contain mistakes; the official description above is the record.