# CVE-2018-7755: Information disclosure in n/a

> An attacker can leak kernel pointers via the floppy driver ioctl to bypass KASLR and discover kernel memory layout.

- **Severity:** Medium 5.5 (`CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 Mar 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-7755, GHSA-446x-f9hh-hqmm, UBUNTU-CVE-2018-7755

## What is CVE-2018-7755?

CVE-2018-7755 is a medium-severity vulnerability in Canonical Ubuntu Linux, published on 8 Mar 2018. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An issue was discovered in the fd_locked_ioctl function in drivers/block/floppy.c in the Linux kernel through 4.15.7. The floppy driver will copy a kernel pointer to user memory in response to the FDGETPRM ioctl. An attacker can send the FDGETPRM ioctl and use the obtained kernel pointer to discover the location of kernel code and data and bypass kernel security protections such as KASLR.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2018-7755?

It affects 2 products.


Products: Canonical Ubuntu Linux, Linux kernel.

## How do I fix CVE-2018-7755?

Apply the vendor's patch.

## Is CVE-2018-7755 being exploited?

There is no known exploitation of CVE-2018-7755 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-2018-7755 and fix it if it is affected.

What it is: CVE-2018-7755 is a medium-severity vulnerability in Canonical Ubuntu Linux, published on 8 Mar 2018. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-7755 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-2018-7755/ (Markdown: https://insights.sbomify.com/CVE-2018-7755/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-7755
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-7755
- OSV: https://osv.dev/vulnerability/CVE-2018-7755

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-7755/
Summaries are generated and may contain mistakes; the official description above is the record.