# CVE-2018-9838: Integer overflow in n/a

> Integer overflow in OCaml's bigarray deserialization allows remote attackers to cause denial of service or execute arbitrary code via crafted marshalled data.

- **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:** 6 Apr 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-9838, GHSA-wc7m-73fq-26mj, MGASA-2019-0124, OSEC-2018-01, SUSE-SU-2018:0983-1, SUSE-SU-2018:1075-1, SUSE-SU-2018:1493-1, SUSE-SU-2018:1494-1, UBUNTU-CVE-2018-9838

## What is CVE-2018-9838?

CVE-2018-9838 is a critical vulnerability in n/a, published on 6 Apr 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The caml_ba_deserialize function in byterun/bigarray.c in the standard library in OCaml 4.06.0 has an integer overflow which, in situations where marshalled data is accepted from an untrusted source, allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbitrary code via a crafted object.

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2018-9838?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ocaml` | SUSE:Linux Enterprise Software Development Kit 11 SP4 | All versions | 4.02.1-4.3.2 |
| `ocaml` | SUSE:Linux Enterprise Software Development Kit 11 SP4 | All versions | 4.02.1-4.6.1 |
| `ocaml` | SUSE:Linux Enterprise Software Development Kit 12 SP3 | All versions | 4.03.0-8.3.1 |
| `ocaml` | SUSE:Linux Enterprise Software Development Kit 12 SP3 | All versions | 4.03.0-8.6.8 |

Products: Ocaml Ocaml.

## How do I fix CVE-2018-9838?

Apply the vendor's patch.

## Is CVE-2018-9838 being exploited?

There is no known exploitation of CVE-2018-9838 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2017-9772](https://insights.sbomify.com/CVE-2017-9772/): Privilege escalation in n/a (critical 9.8)
- [CVE-2026-28364](https://insights.sbomify.com/CVE-2026-28364/): Memory corruption in OCaml (high 7.9)
- [CVE-2017-9779](https://insights.sbomify.com/CVE-2017-9779/): Other in n/a (high 7.8)
- [CVE-2026-34353](https://insights.sbomify.com/CVE-2026-34353/): Integer overflow in OCaml (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-9838 and fix it if it is affected.

What it is: CVE-2018-9838 is a critical vulnerability in n/a, published on 6 Apr 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-2018-9838 in the wild and no public exploit code.

Affected product: n/a. 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-2018-9838/ (Markdown: https://insights.sbomify.com/CVE-2018-9838/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-9838
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-9838
- OSV: https://osv.dev/vulnerability/CVE-2018-9838

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-9838/
Summaries are generated and may contain mistakes; the official description above is the record.