# CVE-2026-5747: Out-of-bounds Write in Firecracker virtio-pci Transport

> CVE-2026-5747: Out-of-bounds Write in Firecracker virtio-pci Transport. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-5747
Last updated: 2026-07-24T09:10:00Z

- Published: 2026-04-07 23:17 UTC · Updated: 2026-07-24 09:10 UTC · Assigner: AMZN
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
- EPSS: 0.26%, 17th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-369, CWE-787

## Description

An out-of-bounds write issue in the virtio PCI transport in Firecracker 1.13.0 through 1.14.3 and 1.15.0 on x86\_64 and aarch64 might allow a local guest user with root privileges to crash the Firecracker VMM process or potentially execute arbitrary code on the host via modification of virtio queue configuration registers after device activation. Achieving code execution on the host requires additional preconditions, such as the use of a custom guest kernel or specific snapshot configurations. To remediate this, users should upgrade to Firecracker 1.14.4 or 1.15.1 and later.

## Affected vendors and products

- AWS: Firecracker

## Tracked companies

- [Amazon Web Services](https://rewindex.com/company/aws.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-5747)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-5747)
- [https://aws.amazon.com/security/security-bulletins/2026-015-aws/](https://aws.amazon.com/security/security-bulletins/2026-015-aws/)
- [https://github.com/firecracker-microvm/firecracker/releases/tag/v1.14.4](https://github.com/firecracker-microvm/firecracker/releases/tag/v1.14.4)
- [https://github.com/firecracker-microvm/firecracker/releases/tag/v1.15.1](https://github.com/firecracker-microvm/firecracker/releases/tag/v1.15.1)
- [https://github.com/firecracker-microvm/firecracker/security/advisories/GHSA-776c-mpj7-jm3r](https://github.com/firecracker-microvm/firecracker/security/advisories/GHSA-776c-mpj7-jm3r)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-5747 · Markdown: https://rewindex.com/cve/CVE-2026-5747.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-5747 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:50:12.287Z