# CVE-2026-74222: U-Boot before 2026.10-rc5 Use-After-Free in lwIP wget Receive Callback

> A use-after-free in U-Boot's lwIP wget callback causes a crash when HTTP data storage fails, leading to denial of service.

- **Severity:** High 8.8 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 29 Sep 2026
- **Updated:** 2 Oct 2026
- **Also known as:** GHSA-fm4f-g9jh-3qfq, UBUNTU-CVE-2026-74222

## What is CVE-2026-74222?

CVE-2026-74222 is a high-severity use after free vulnerability in u-boot, published on 29 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

U-Boot before 2026.10-rc5 contains a use-after-free vulnerability in the httpc_recv_cb() function within the lwIP wget implementation. When HTTP data storage fails, the callback frees the connection PCB but returns ERR_BUF instead of ERR_ABRT, causing the TCP input path to access released memory and crash the bootloader.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-74222?


## How do I fix CVE-2026-74222?

Upgrade to a fixed version.

## Is CVE-2026-74222 being exploited?

There is no known exploitation of CVE-2026-74222 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74222 and fix it if it is affected.

What it is: CVE-2026-74222 is a high-severity use after free vulnerability in u-boot, published on 29 Sep 2026. 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-2026-74222 in the wild and no public exploit code.

Affected product: u-boot. 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-2026-74222/ (Markdown: https://insights.sbomify.com/CVE-2026-74222/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74222
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74222
- OSV: https://osv.dev/vulnerability/CVE-2026-74222

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74222/
Summaries are generated and may contain mistakes; the official description above is the record.