# CVE-2018-5388: Denial of service in strongSwan

> A missing packet length check in strongSwan allows attackers to cause resource exhaustion and denial of service via socket reading.

- **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:** 31 May 2018
- **Updated:** 5 Aug 2024
- **Also known as:** ALPINE-CVE-2018-5388, DEBIAN-CVE-2018-5388, GHSA-fg62-299p-x79j, UBUNTU-CVE-2018-5388

## What is CVE-2018-5388?

CVE-2018-5388 is a medium-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 31 May 2018. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

In stroke_socket.c in strongSwan before 5.6.3, a missing packet length check could allow a buffer underflow, which may lead to resource exhaustion and denial of service while reading from the socket.

Weakness: CWE-787 (Out-of-bounds Write), CWE-124 (Buffer Underwrite)

## Which versions are affected by CVE-2018-5388?

It affects 3 products.


Products: Canonical Ubuntu Linux, Debian Debian Linux, Strongswan Strongswan.

## How do I fix CVE-2018-5388?

Upgrade to a fixed version.

## Is CVE-2018-5388 being exploited?

There is no known exploitation of CVE-2018-5388 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-2018-5388 and fix it if it is affected.

What it is: CVE-2018-5388 is a medium-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 31 May 2018. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-5388 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-2018-5388/ (Markdown: https://insights.sbomify.com/CVE-2018-5388/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-5388
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-5388
- OSV: https://osv.dev/vulnerability/CVE-2018-5388

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-5388/
Summaries are generated and may contain mistakes; the official description above is the record.