# CVE-2018-18309: Null dereference in n/a

> An attacker can cause a denial of service via a segmentation fault in the BFD library when processing malformed binary files with tools like objdump.

- **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:** 15 Oct 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-18309, GHSA-cqf4-rwmp-9g9j, UBUNTU-CVE-2018-18309

## What is CVE-2018-18309?

CVE-2018-18309 is a medium-severity vulnerability in Gnu Binutils, published on 15 Oct 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 the Binary File Descriptor (BFD) library (aka libbfd), as distributed in GNU Binutils 2.31. An invalid memory address dereference was discovered in read_reloc in reloc.c. The vulnerability causes a segmentation fault and application crash, which leads to denial of service, as demonstrated by objdump, because of missing _bfd_clear_contents bounds checking.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2018-18309?

It affects 1 product.


Products: Gnu Binutils.

## How do I fix CVE-2018-18309?

Apply the vendor's patch.

## Is CVE-2018-18309 being exploited?

There is no known exploitation of CVE-2018-18309 in the wild and no public exploit code.

## Other vulnerabilities in Gnu Binutils

- [CVE-2017-7614](https://insights.sbomify.com/CVE-2017-7614/): Null dereference in n/a (critical 9.8)
- [CVE-2014-9939](https://insights.sbomify.com/CVE-2014-9939/): Memory corruption in n/a (critical 9.8)
- [CVE-2017-7226](https://insights.sbomify.com/CVE-2017-7226/): Information disclosure in n/a (critical 9.1)
- [CVE-2017-6969](https://insights.sbomify.com/CVE-2017-6969/): Information disclosure in n/a (critical 9.1)
- [CVE-2020-19726](https://insights.sbomify.com/CVE-2020-19726/): Denial of service in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-18309 and fix it if it is affected.

What it is: CVE-2018-18309 is a medium-severity vulnerability in Gnu Binutils, published on 15 Oct 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-2018-18309 in the wild and no public exploit code.

Affected product: Gnu Binutils. 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-2018-18309/ (Markdown: https://insights.sbomify.com/CVE-2018-18309/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-18309
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-18309
- OSV: https://osv.dev/vulnerability/CVE-2018-18309

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-18309/
Summaries are generated and may contain mistakes; the official description above is the record.