# CVE-2026-86847: Dpdk: dpdk: guest can trigger infinite loop in vhost-crypto writeback chain cleanup

> A guest can trigger an infinite loop or crash in the host vhost-crypto process by causing a mapping failure that leads to following an uninitialized pointer.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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:** 14 Oct 2026
- **Updated:** 20 Oct 2026
- **Also known as:** AZL-108327, DEBIAN-CVE-2026-86847, GHSA-88x8-5995-vmmf, UBUNTU-CVE-2026-86847

## What is CVE-2026-86847?

CVE-2026-86847 is a medium-severity vulnerability in Red Hat Fast Datapath for RHEL 10, published on 14 Oct 2026. 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 DPDK lib/vhost vhost-crypto. Write-back chain cleanup can follow an uninitialized next pointer when mapping a guest descriptor fails, causing the host vhost-crypto process to hang or crash.

Weakness: CWE-824 (Access of Uninitialized Pointer)

## Which versions are affected by CVE-2026-86847?


## How do I fix CVE-2026-86847?

Apply the vendor's patch.

## Is CVE-2026-86847 being exploited?

There is no known exploitation of CVE-2026-86847 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-86847 and fix it if it is affected.

What it is: CVE-2026-86847 is a medium-severity vulnerability in Red Hat Fast Datapath for RHEL 10, published on 14 Oct 2026. 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-2026-86847 in the wild and no public exploit code.

Affected product: Red Hat Fast Datapath for RHEL 10. 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-2026-86847/ (Markdown: https://insights.sbomify.com/CVE-2026-86847/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-86847
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-86847
- OSV: https://osv.dev/vulnerability/CVE-2026-86847

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-86847/
Summaries are generated and may contain mistakes; the official description above is the record.