# CVE-2017-17817: Use after free in n/a

> A use-after-free flaw in Netwide Assembler allows remote attackers to cause a denial of service via crafted input.

- **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:** Yes
- **Published:** 21 Dec 2017
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2017-17817, GHSA-2v7v-w7p2-84j7, UBUNTU-CVE-2017-17817

## What is CVE-2017-17817?

CVE-2017-17817 is a medium-severity use after free vulnerability in Canonical Ubuntu Linux, published on 21 Dec 2017. 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

In Netwide Assembler (NASM) 2.14rc0, there is a use-after-free in pp_verror in asm/preproc.c that will cause a remote denial of service attack.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2017-17817?

It affects 2 products.


Products: Canonical Ubuntu Linux, Nasm Netwide Assembler.

## How do I fix CVE-2017-17817?

Upgrade to a fixed version.

## Is CVE-2017-17817 being exploited?

There is no known exploitation of CVE-2017-17817 in the wild and no public exploit code.

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-17817 and fix it if it is affected.

What it is: CVE-2017-17817 is a medium-severity use after free vulnerability in Canonical Ubuntu Linux, published on 21 Dec 2017. 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-2017-17817 in the wild and no public exploit code.

Affected product: Canonical Ubuntu Linux. 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-2017-17817/ (Markdown: https://insights.sbomify.com/CVE-2017-17817/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-17817
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-17817
- OSV: https://osv.dev/vulnerability/CVE-2017-17817

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-17817/
Summaries are generated and may contain mistakes; the official description above is the record.