# CVE-2019-20007: Null dereference in n/a

> A crafted XML file causes a NULL pointer dereference in the ezXML library, leading to a segmentation fault and denial of service.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/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:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 26 Dec 2019
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-20007, GHSA-27qv-mw67-9whg, UBUNTU-CVE-2019-20007

## What is CVE-2019-20007?

CVE-2019-20007 is a medium-severity vulnerability in n/a, published on 26 Dec 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

An issue was discovered in ezXML 0.8.2 through 0.8.6. The function ezxml_str2utf8, while parsing a crafted XML file, performs zero-length reallocation in ezxml.c, leading to returning a NULL pointer (in some compilers). After this, the function ezxml_parse_str does not check whether the s variable is not NULL in ezxml.c, leading to a NULL pointer dereference and crash (segmentation fault).

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2019-20007?

It affects 1 product.


Products: Ezxml Project Ezxml.

## How do I fix CVE-2019-20007?

Upgrade to a fixed version.

## Is CVE-2019-20007 being exploited?

There is no known exploitation of CVE-2019-20007 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-26220](https://insights.sbomify.com/CVE-2021-26220/): Memory corruption in n/a (high 8.1)
- [CVE-2021-26221](https://insights.sbomify.com/CVE-2021-26221/): Memory corruption in n/a (high 8.1)
- [CVE-2021-26222](https://insights.sbomify.com/CVE-2021-26222/): Memory corruption in n/a (high 8.1)
- [CVE-2019-20006](https://insights.sbomify.com/CVE-2019-20006/): Use after free in n/a (high 7.5)
- [CVE-2022-30045](https://insights.sbomify.com/CVE-2022-30045/): Memory corruption in n/a (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-20007 and fix it if it is affected.

What it is: CVE-2019-20007 is a medium-severity vulnerability in n/a, published on 26 Dec 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2019-20007 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-2019-20007/ (Markdown: https://insights.sbomify.com/CVE-2019-20007/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-20007
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-20007
- OSV: https://osv.dev/vulnerability/CVE-2019-20007

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-20007/
Summaries are generated and may contain mistakes; the official description above is the record.