# CVE-2021-40154: Information disclosure in n/a

> An attacker with physical access can read protected flash memory via a crafted USB request during ISP mode on NXP LPC55S69 devices.

- **Severity:** Medium 6.1 (`CVSS:3.1/AC:L/AV:L/A:L/C:H/I:N/PR:L/S:U/UI:N`)
- **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:** No
- **Published:** 1 Dec 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-f88h-2xxc-h4r4

## What is CVE-2021-40154?

CVE-2021-40154 is a medium-severity vulnerability in n/a, published on 1 Dec 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

NXP LPC55S69 devices before A3 have a buffer over-read via a crafted wlength value in a GET Descriptor Configuration request during use of USB In-System Programming (ISP) mode. This discloses protected flash memory.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2021-40154?

It affects 3 products.


Products: Nxp Lpc55s69jbd100 Firmware, Nxp Lpc55s69jbd64 Firmware, Nxp Lpc55s69jev98 Firmware.

## How do I fix CVE-2021-40154?

No fix has been published for CVE-2021-40154 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-40154 being exploited?

There is no known exploitation of CVE-2021-40154 in the wild and no public exploit code.

Public exploit code:

- POC to test the BootROM vulnerability found in LPC55S69 and K82 Series  (github_poc): https://github.com/Jeromeyoung/CVE-2021-40154

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-40154 and fix it if it is affected.

What it is: CVE-2021-40154 is a medium-severity vulnerability in n/a, published on 1 Dec 2021. 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-2021-40154 in the wild and no public exploit code.

Affected product: n/a. 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-2021-40154/ (Markdown: https://insights.sbomify.com/CVE-2021-40154/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-40154
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-40154
- OSV: https://osv.dev/vulnerability/CVE-2021-40154

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-40154/
Summaries are generated and may contain mistakes; the official description above is the record.