# CVE-2026-86847: DPDK vhost-crypto uninitialized pointer in write-back chain

Source: https://junglewise.ai/threats/cve-2026-86847-a-flaw-was-found-in-dpdk-lib-vhost-vhost-crypto-write-back-chain  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-14. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-86847 · Severity: medium · CVSS 6.5 · Published 2026-10-14

DPDK is a library used to accelerate packet processing in data plane applications. A flaw in the vhost-crypto component can cause the vhost-crypto process to hang or crash when a guest virtual machine with a virtio-crypto device sends specially crafted requests. This results in denial of service affecting virtualized networking and packet processing.

Technologies: [DPDK](https://junglewise.ai/threats/technologies/dpdk). Vendors: [DPDK](https://junglewise.ai/threats/vendors/dpdk).

## Quick answers

**Is CVE-2026-86847 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-86847 being exploited in the wild.

**How severe is CVE-2026-86847?** Medium severity, with a CVSS score of 6.5, published 14 October 2026.

**Which products and versions are affected?** DPDK DPDK.

**Is there a fix for CVE-2026-86847?** No fixed version is recorded yet. Do not attach a virtio-crypto vhost-user backend to untrusted guests. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-86847 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-86847?** Check whether you run DPDK. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix


Do not attach a virtio-crypto vhost-user backend to untrusted guests.

## Technical details

The vulnerability exists in DPDK lib/vhost vhost-crypto where write-back chain cleanup follows an uninitialized next pointer when mapping a guest descriptor fails. This is a CWE-824 (access of uninitialized pointer) issue triggered by a local guest with a virtio-crypto vhost-user device, requiring low privileges. An attacker can cause the host vhost-crypto process to hang or crash, achieving denial of service.

## Affected products

- DPDK DPDK

## Timeline

- 2026-10-14: disclosed

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-86847](https://access.redhat.com/security/cve/CVE-2026-86847)

## Related threats

- [DPDK vhost-crypto integer overflow in lib/vhost](https://junglewise.ai/threats/cve-2026-86849-a-flaw-was-found-in-dpdk-lib-vhost-vhost-crypto-integer-overflow)
- [DPDK vhost-crypto indirect-descriptor double-fetch out-of-bounds](https://junglewise.ai/threats/cve-2026-86848-a-flaw-was-found-in-dpdk-lib-vhost-vhost-crypto-the-indirect)
- [DPDK vhost-crypto out-of-bounds write via unchecked descriptor index](https://junglewise.ai/threats/cve-2026-86846-a-flaw-was-found-in-dpdk-lib-vhost-vhost-crypto-a-guest-can)
- [DPDK lib/vhost use-after-free in VDUSE handler](https://junglewise.ai/threats/cve-2026-86567-a-flaw-was-found-in-dpdk-lib-vhost-the-vduse-handler-fails-to)
- [DPDK lib/vhost integer underflow in RX descriptor processing](https://junglewise.ai/threats/cve-2026-86566-a-flaw-was-found-in-dpdk-lib-vhost-a-guest-with-runt-rx)