# CVE-2018-5187: Memory corruption in Firefox

> Memory safety bugs in Firefox and Thunderbird allow attackers to execute arbitrary code via crafted web content.

- **Severity:** Critical 9.8 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Oct 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-5187, GHSA-3w2h-f87x-m6vp, UBUNTU-CVE-2018-5187

## What is CVE-2018-5187?

CVE-2018-5187 is a critical memory corruption vulnerability in Canonical Ubuntu Linux, published on 18 Oct 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Memory safety bugs present in Firefox 60 and Firefox ESR 60. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Thunderbird < 60, Firefox ESR < 60.1, and Firefox < 61.

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

## Which versions are affected by CVE-2018-5187?

It affects 4 products.


Products: Canonical Ubuntu Linux, Debian Debian Linux, Mozilla Firefox, Mozilla Thunderbird.

## How do I fix CVE-2018-5187?

Upgrade to a fixed version.

## Is CVE-2018-5187 being exploited?

There is no known exploitation of CVE-2018-5187 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-2018-5187 and fix it if it is affected.

What it is: CVE-2018-5187 is a critical memory corruption vulnerability in Canonical Ubuntu Linux, published on 18 Oct 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-5187 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-2018-5187/ (Markdown: https://insights.sbomify.com/CVE-2018-5187/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-5187
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-5187
- OSV: https://osv.dev/vulnerability/CVE-2018-5187

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-5187/
Summaries are generated and may contain mistakes; the official description above is the record.