# CVE-2017-2618: Null dereference in kernel

> An attacker can crash the Linux kernel by writing null bytes to SELinux attribute files, causing a system-wide denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.0/AV:L/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Jul 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2017-2618, GHSA-hpw2-j46j-hpv2, UBUNTU-CVE-2017-2618

## What is CVE-2017-2618?

CVE-2017-2618 is a medium-severity vulnerability in Debian Debian Linux, published on 27 Jul 2018. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in the Linux kernel's handling of clearing SELinux attributes on /proc/pid/attr files before 4.9.10. An empty (null) write to this file can crash the system by causing the system to attempt to access unmapped kernel memory.

Weakness: CWE-682 (Incorrect Calculation), CWE-193 (Off-by-one Error)

## Which versions are affected by CVE-2017-2618?

It affects 8 products.


Products: Debian Debian Linux, Linux kernel, Redhat Enterprise Linux, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus, Redhat Enterprise Linux Workstation.

## How do I fix CVE-2017-2618?

Apply the vendor's patch.

## Is CVE-2017-2618 being exploited?

There is no known exploitation of CVE-2017-2618 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-2017-2618 and fix it if it is affected.

What it is: CVE-2017-2618 is a medium-severity vulnerability in Debian Debian Linux, published on 27 Jul 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-2017-2618 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-2017-2618/ (Markdown: https://insights.sbomify.com/CVE-2017-2618/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-2618
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-2618
- OSV: https://osv.dev/vulnerability/CVE-2017-2618

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-2618/
Summaries are generated and may contain mistakes; the official description above is the record.