# CVE-2018-20374: Memory corruption in n/a

> An attacker can cause an out-of-bounds write in Tiny C Compiler by providing a crafted source file, potentially leading to code execution or crashes.

- **Severity:** Medium 5.5 (`CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 23 Dec 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-20374, GHSA-c6x3-v6cq-j2qh, UBUNTU-CVE-2018-20374

## What is CVE-2018-20374?

CVE-2018-20374 is a medium-severity memory corruption vulnerability in n/a, published on 23 Dec 2018. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

An issue was discovered in Tiny C Compiler (aka TinyCC or TCC) 0.9.27. Compiling a crafted source file leads to an 8 byte out of bounds write in the use_section1 function in tccasm.c.

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

## Which versions are affected by CVE-2018-20374?

It affects 1 product.


Products: Tinycc Tinycc.

## How do I fix CVE-2018-20374?

No fix has been published for CVE-2018-20374 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-20374 being exploited?

There is no known exploitation of CVE-2018-20374 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2019-12495](https://insights.sbomify.com/CVE-2019-12495/): Memory corruption in n/a (medium 5.5)
- [CVE-2019-9754](https://insights.sbomify.com/CVE-2019-9754/): Memory corruption in n/a (medium 5.5)
- [CVE-2018-20375](https://insights.sbomify.com/CVE-2018-20375/): Memory corruption in n/a (medium 5.5)
- [CVE-2018-20376](https://insights.sbomify.com/CVE-2018-20376/): Memory corruption in n/a (medium 5.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-20374 and fix it if it is affected.

What it is: CVE-2018-20374 is a medium-severity memory corruption vulnerability in n/a, published on 23 Dec 2018. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2018-20374 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-2018-20374/ (Markdown: https://insights.sbomify.com/CVE-2018-20374/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-20374
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-20374
- OSV: https://osv.dev/vulnerability/CVE-2018-20374

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-20374/
Summaries are generated and may contain mistakes; the official description above is the record.