# CVE-2026-23326: xsk: Fix fragment node deletion to prevent buffer leak

> A logic error in the Linux kernel's XSK fragment handling causes buffer leaks, potentially leading to resource exhaustion and denial of service.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Mar 2026
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2026-23326, DEBIAN-CVE-2026-23326, GHSA-6r9h-pc2x-g962, UBUNTU-CVE-2026-23326

## What is CVE-2026-23326?

CVE-2026-23326 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

xsk: Fix fragment node deletion to prevent buffer leak

After commit b692bf9a7543 ("xsk: Get rid of xdp_buff_xsk::xskb_list_node"),
the list_node field is reused for both the xskb pool list and the buffer
free list, this causes a buffer leak as described below.

xp_free() checks if a buffer is already on the free list using
list_empty(&xskb->list_node). When list_del() is used to remove a node
from the xskb pool list, it doesn't reinitialize the node pointers.
This means list_empty() will return false even after the node has been
removed, causing xp_free() to incorrectly skip adding the buffer to the
free list.

Fix this by using list_del_init() instead of list_del() in all fragment
handling paths, this ensures the list node is reinitialized after removal,
allowing the list_empty() to work correctly.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-23326?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-23326?

Apply the vendor's patch.

## Is CVE-2026-23326 being exploited?

There is no known exploitation of CVE-2026-23326 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-2026-23326 and fix it if it is affected.

What it is: CVE-2026-23326 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-23326 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-2026-23326/ (Markdown: https://insights.sbomify.com/CVE-2026-23326/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23326
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23326
- OSV: https://osv.dev/vulnerability/CVE-2026-23326

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23326/
Summaries are generated and may contain mistakes; the official description above is the record.