# CVE-2018-10242: Memory corruption in n/a

> A malformed SSH banner causes Suricata to read beyond allocated memory, potentially leading to a denial of service.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/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:** Yes
- **Published:** 4 Apr 2019
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-10242, GHSA-xrxh-g8jf-mf2m, UBUNTU-CVE-2018-10242

## What is CVE-2018-10242?

CVE-2018-10242 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 4 Apr 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Suricata version 4.0.4 incorrectly handles the parsing of the SSH banner. A malformed SSH banner can cause the parsing code to read beyond the allocated data because SSHParseBanner in app-layer-ssh.c lacks a length check.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2018-10242?

It affects 2 products.


Products: Debian Debian Linux, Oisf Suricata.

## How do I fix CVE-2018-10242?

Upgrade to a fixed version.

## Is CVE-2018-10242 being exploited?

There is no known exploitation of CVE-2018-10242 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-10242 and fix it if it is affected.

What it is: CVE-2018-10242 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 4 Apr 2019. 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-2018-10242 in the wild and no public exploit code.

Affected product: Debian Debian 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-2018-10242/ (Markdown: https://insights.sbomify.com/CVE-2018-10242/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-10242
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-10242
- OSV: https://osv.dev/vulnerability/CVE-2018-10242

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-10242/
Summaries are generated and may contain mistakes; the official description above is the record.