# CVE-2018-5389: CVE-2018-5389

> Attackers can recover weak Pre-Shared Keys or impersonate hosts via offline brute-force attacks against IKEv1 main mode.

- **Severity:** Medium 5.9 (`CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Sep 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-5389, GHSA-999m-cq5c-hqgx, UBUNTU-CVE-2018-5389

## What is CVE-2018-5389?

CVE-2018-5389 is a medium-severity vulnerability in Strongswan, published on 6 Sep 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Internet Key Exchange v1 main mode is vulnerable to offline dictionary or brute force attacks. Reusing a key pair across different versions and modes of IKE could lead to cross-protocol authentication bypasses. It is well known, that the aggressive mode of IKEv1 PSK is vulnerable to offline dictionary or brute force attacks. For the main mode, however, only an online attack against PSK authentication was thought to be feasible. This vulnerability could allow an attacker to recover a weak Pre-Shared Key or enable the impersonation of a victim host or network.

Weakness: CWE-521 (Weak Password Requirements)

## Which versions are affected by CVE-2018-5389?

It affects 1 product.


Products: Ietf Internet Key Exchange.

## How do I fix CVE-2018-5389?

No fix has been published for CVE-2018-5389 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-5389 being exploited?

There is no known exploitation of CVE-2018-5389 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-5389 and fix it if it is affected.

What it is: CVE-2018-5389 is a medium-severity vulnerability in Strongswan, published on 6 Sep 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-2018-5389 in the wild and no public exploit code.

Affected product: Strongswan. 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-2018-5389/ (Markdown: https://insights.sbomify.com/CVE-2018-5389/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-5389
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-5389
- OSV: https://osv.dev/vulnerability/CVE-2018-5389

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-5389/
Summaries are generated and may contain mistakes; the official description above is the record.