# CVE-2026-29009: U-Boot < 2026.07-rc2 Buffer Overflow in nfs_readlink_reply() via NFS READLINK

> A malicious NFS server can trigger a buffer overflow in U-Boot's NFS client, potentially leading to memory corruption and code execution during boot.

- **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:** 8 Jul 2026
- **Updated:** 24 Jul 2026
- **Also known as:** DEBIAN-CVE-2026-29009, GHSA-rqrq-75p3-gc68, OESA-2026-2994, UBUNTU-CVE-2026-29009

## What is CVE-2026-29009?

CVE-2026-29009 is a high-severity memory corruption vulnerability in u-boot, published on 8 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

U-Boot before 2026.07-rc2 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input)

## Which versions are affected by CVE-2026-29009?

It affects 1 product.


Products: Denx U-Boot.

## How do I fix CVE-2026-29009?

Upgrade to a fixed version.

## Is CVE-2026-29009 being exploited?

There is no known exploitation of CVE-2026-29009 in the wild and no public exploit code.

## Other vulnerabilities in u-boot

- [CVE-2022-34835](https://insights.sbomify.com/CVE-2022-34835/): Integer overflow in n/a (critical 9.8)
- [CVE-2022-30767](https://insights.sbomify.com/CVE-2022-30767/): Memory corruption in n/a (critical 9.8)
- [CVE-2020-8432](https://insights.sbomify.com/CVE-2020-8432/): Use after free in n/a (critical 9.8)
- [CVE-2019-14192](https://insights.sbomify.com/CVE-2019-14192/): Integer overflow in n/a (critical 9.8)
- [CVE-2019-14193](https://insights.sbomify.com/CVE-2019-14193/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-29009 and fix it if it is affected.

What it is: CVE-2026-29009 is a high-severity memory corruption vulnerability in u-boot, published on 8 Jul 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-2026-29009 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-2026-29009/ (Markdown: https://insights.sbomify.com/CVE-2026-29009/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-29009
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-29009
- OSV: https://osv.dev/vulnerability/CVE-2026-29009

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-29009/
Summaries are generated and may contain mistakes; the official description above is the record.