# CVE-2026-53091: net: pull headers in qdisc_pkt_len_segs_init()

> A missing header pull in Linux kernel qdisc handling allows malicious GSO packets to cause memory corruption or crashes.

- **Severity:** High 8.4 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/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:** 24 Jun 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-90438, BELL-CVE-2026-53091, DEBIAN-CVE-2026-53091, GHSA-mjfm-6cr9-5cqx, ROOT-OS-DEBIAN-11-CVE-2026-53091, ROOT-OS-DEBIAN-12-CVE-2026-53091, ROOT-OS-DEBIAN-13-CVE-2026-53091, ROOT-OS-UBUNTU-2204-CVE-2026-53091, ROOT-OS-UBUNTU-2404-CVE-2026-53091, UBUNTU-CVE-2026-53091

## What is CVE-2026-53091?

CVE-2026-53091 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 Jun 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:

net: pull headers in qdisc_pkt_len_segs_init()

Most ndo_start_xmit() methods expects headers of gso packets
to be already in skb->head.

net/core/tso.c users are particularly at risk, because tso_build_hdr()
does a memcpy(hdr, skb->data, hdr_len);

qdisc_pkt_len_segs_init() already does a dissection of gso packets.

Use pskb_may_pull() instead of skb_header_pointer() to make
sure drivers do not have to reimplement this.

Some malicious packets could be fed, detect them so that we can
drop them sooner with a new SKB_DROP_REASON_SKB_BAD_GSO drop_reason.

Weakness: CWE-131 (Incorrect Calculation of Buffer Size)

## Which versions are affected by CVE-2026-53091?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53091?

Apply the vendor's patch.

## Is CVE-2026-53091 being exploited?

There is no known exploitation of CVE-2026-53091 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-2026-53091 and fix it if it is affected.

What it is: CVE-2026-53091 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 Jun 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-2026-53091 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-2026-53091/ (Markdown: https://insights.sbomify.com/CVE-2026-53091/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53091
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53091
- OSV: https://osv.dev/vulnerability/CVE-2026-53091

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53091/
Summaries are generated and may contain mistakes; the official description above is the record.