# CVE-2018-18056: Information disclosure in n/a

> Attackers can reverse-engineer protected firmware instructions on TI microcontrollers by single-stepping through XOM-protected memory to observe state changes.

- **Severity:** Medium 4.6 (`CVSS:3.0/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Aug 2019
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-9wjv-55xx-m5xp

## What is CVE-2018-18056?

CVE-2018-18056 is a medium-severity vulnerability in n/a, published on 20 Aug 2019. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An issue was discovered in the Texas Instruments (TI) TM4C, MSP432E and MSP432P microcontroller series. The eXecute-Only-Memory (XOM) implementation prevents code read-outs on protected memory by generating bus faults. However, single-stepping and using breakpoints is allowed in XOM-protected flash memory. As a consequence, it is possible to execute single instructions with arbitrary system states (e.g., registers, status flags, and SRAM content) and observe the state changes produced by the unknown instruction. An attacker could exploit this vulnerability by executing protected and unknown instructions with specific system states and observing the state changes. Based on the gathered information, it is possible to reverse-engineer the executed instructions. The processor acts as a kind of "instruction oracle."

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2018-18056?

It affects 2 products.


Products: Ti Tm4c123 Firmware, Ti Tm4c129 Firmware.

## How do I fix CVE-2018-18056?

No fix has been published for CVE-2018-18056 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-18056 being exploited?

There is no known exploitation of CVE-2018-18056 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-18056 and fix it if it is affected.

What it is: CVE-2018-18056 is a medium-severity vulnerability in n/a, published on 20 Aug 2019. 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-2018-18056 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-2018-18056/ (Markdown: https://insights.sbomify.com/CVE-2018-18056/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-18056
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-18056
- OSV: https://osv.dev/vulnerability/CVE-2018-18056

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-18056/
Summaries are generated and may contain mistakes; the official description above is the record.