# CVE-2018-1091: Denial of service in Linux kernel v4.13 and newer

> Unprivileged userspace can crash the guest kernel on POWER hosts during core dumps due to missing transactional memory feature checks.

- **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 Mar 2018
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2018-1091, GHSA-8x9x-6w2w-w9h8

## What is CVE-2018-1091?

CVE-2018-1091 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Mar 2018. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the flush_tmregs_to_thread function in arch/powerpc/kernel/ptrace.c in the Linux kernel before 4.13.5, a guest kernel crash can be triggered from unprivileged userspace during a core dump on a POWER host due to a missing processor feature check and an erroneous use of transactional memory (TM) instructions in the core dump path, leading to a denial of service.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), CWE-391 (DEPRECATED: Unchecked Error Condition)

## Which versions are affected by CVE-2018-1091?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2018-1091?

Apply the vendor's patch.

## Is CVE-2018-1091 being exploited?

There is no known exploitation of CVE-2018-1091 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-1091 and fix it if it is affected.

What it is: CVE-2018-1091 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 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-2018-1091 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2018-1091/ (Markdown: https://insights.sbomify.com/CVE-2018-1091/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-1091
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-1091
- OSV: https://osv.dev/vulnerability/CVE-2018-1091

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-1091/
Summaries are generated and may contain mistakes; the official description above is the record.