# CVE-2011-2723: Denial of service in n/a

> Remote attackers can cause a system crash via crafted network traffic when Generic Receive Offload is enabled in the Linux kernel.

- **Severity:** Medium 5.7 (`AV:A/AC:M/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:** 6 Sep 2011
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-gj23-gxgc-vvhj, RHSA-2011:1321

## What is CVE-2011-2723?

CVE-2011-2723 is a medium-severity denial of service vulnerability in Linux kernel, published on 6 Sep 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The skb_gro_header_slow function in include/linux/netdevice.h in the Linux kernel before 2.6.39.4, when Generic Receive Offload (GRO) is enabled, resets certain fields in incorrect situations, which allows remote attackers to cause a denial of service (system crash) via crafted network traffic.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2011-2723?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `kernel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-PAE` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-PAE-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-PAE-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-debug` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-debug-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-debug-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-debuginfo-common` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-doc` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-headers` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-kdump` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-kdump-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-kdump-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-xen` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-xen-debuginfo` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |
| `kernel-xen-devel` | Red Hat:enterprise_linux:5::server | All versions | 0:2.6.18-238.27.1.el5 |

Products: Linux kernel.

## How do I fix CVE-2011-2723?

Upgrade to a fixed version.

## Is CVE-2011-2723 being exploited?

There is no known exploitation of CVE-2011-2723 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-2011-2723 and fix it if it is affected.

What it is: CVE-2011-2723 is a medium-severity denial of service vulnerability in Linux kernel, published on 6 Sep 2011. 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-2011-2723 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-2011-2723/ (Markdown: https://insights.sbomify.com/CVE-2011-2723/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-2723
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-2723
- OSV: https://osv.dev/vulnerability/CVE-2011-2723

---
From sbomify Insights: https://insights.sbomify.com/CVE-2011-2723/
Summaries are generated and may contain mistakes; the official description above is the record.