# CVE-2019-14871: Null dereference in newlib

> A null pointer dereference in newlib macros can cause a denial of service in production firmware builds due to unchecked memory allocation failures.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Mar 2020
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-14871, GHSA-2q4g-qm2f-cq2j, UBUNTU-CVE-2019-14871

## What is CVE-2019-14871?

CVE-2019-14871 is a medium-severity vulnerability in Red Hat newlib, published on 18 Mar 2020. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The REENT_CHECK macro (see newlib/libc/include/sys/reent.h) as used by REENT_CHECK_TM, REENT_CHECK_MISC, REENT_CHECK_MP and other newlib macros in versions prior to 3.3.0, does not check for memory allocation problems when the DEBUG flag is unset (as is the case in production firmware builds).

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2019-14871?

It affects 1 product.


Products: Newlib Project Newlib.

## How do I fix CVE-2019-14871?

Upgrade to a fixed version.

## Is CVE-2019-14871 being exploited?

There is no known exploitation of CVE-2019-14871 in the wild and no public exploit code.

## Other vulnerabilities in Red Hat newlib

- [CVE-2024-30949](https://insights.sbomify.com/CVE-2024-30949/): Integer overflow in n/a (critical 9.8)
- [CVE-2019-14872](https://insights.sbomify.com/CVE-2019-14872/): Null dereference in newlib (medium 6.5)
- [CVE-2019-14873](https://insights.sbomify.com/CVE-2019-14873/): Null dereference in newlib (medium 6.5)
- [CVE-2019-14874](https://insights.sbomify.com/CVE-2019-14874/): Null dereference in newlib (medium 6.5)
- [CVE-2019-14875](https://insights.sbomify.com/CVE-2019-14875/): Null dereference in newlib (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-14871 and fix it if it is affected.

What it is: CVE-2019-14871 is a medium-severity vulnerability in Red Hat newlib, published on 18 Mar 2020. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2019-14871 in the wild and no public exploit code.

Affected product: Red Hat newlib. 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-2019-14871/ (Markdown: https://insights.sbomify.com/CVE-2019-14871/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-14871
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-14871
- OSV: https://osv.dev/vulnerability/CVE-2019-14871

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-14871/
Summaries are generated and may contain mistakes; the official description above is the record.