# CVE-2020-17528: Apache NuttX (incubating) Out of Bound Write from invalid TCP Urgent length

> An attacker can corrupt memory and potentially execute code or cause denial of service by sending malicious TCP packets with invalid urgent data pointers to Apache NuttX.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Dec 2020
- **Updated:** 13 Feb 2025
- **Also known as:** GHSA-36mq-qwm2-6rpp

## What is CVE-2020-17528?

CVE-2020-17528 is a critical memory corruption vulnerability in Apache NuttX (incubating), published on 9 Dec 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Out-of-bounds Write vulnerability in TCP stack of Apache NuttX (incubating) versions up to and including 9.1.0 and 10.0.0 allows attacker to corrupt memory by supplying arbitrary urgent data pointer offsets within TCP packets including beyond the length of the packet.

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

## Which versions are affected by CVE-2020-17528?

It affects 1 product.


Products: Apache Nuttx.

## How do I fix CVE-2020-17528?

No fix has been published for CVE-2020-17528 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-17528 being exploited?

There is no known exploitation of CVE-2020-17528 in the wild and no public exploit code.

## Other vulnerabilities in Apache NuttX (incubating)

- [CVE-2025-47868](https://insights.sbomify.com/CVE-2025-47868/): Apache NuttX RTOS: tools/bdf-converter.: tools/bdf-converter: Fix loop termination condition. (critical 9.8)
- [CVE-2025-47869](https://insights.sbomify.com/CVE-2025-47869/): Apache NuttX RTOS: examples/xmlrpc: Fix calls buffers size. (critical 9.8)
- [CVE-2025-35003](https://insights.sbomify.com/CVE-2025-35003/): Apache NuttX RTOS: NuttX Bluetooth Stack HCI and UART DoS/RCE Vulnerabilities. (critical 9.8)
- [CVE-2021-26461](https://insights.sbomify.com/CVE-2021-26461/): malloc, realloc and memalign implementations are vulnerable to integer wrap-arounds (critical 9.8)
- [CVE-2020-17529](https://insights.sbomify.com/CVE-2020-17529/): Apache NuttX (incubating) Out of Bound Write from invalid fragmentation offset value specified in the IP header (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-17528 and fix it if it is affected.

What it is: CVE-2020-17528 is a critical memory corruption vulnerability in Apache NuttX (incubating), published on 9 Dec 2020. 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-2020-17528 in the wild and no public exploit code.

Affected product: Apache NuttX (incubating). 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-2020-17528/ (Markdown: https://insights.sbomify.com/CVE-2020-17528/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-17528
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-17528
- OSV: https://osv.dev/vulnerability/CVE-2020-17528

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-17528/
Summaries are generated and may contain mistakes; the official description above is the record.