CVE-2026-5747 HIGH

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

Vendor Aws
Product Firecracker
Weakness CWE-787
Published April 7, 2026
Last update April 20, 2026

CVSS base score

7.5/10
Attack vector Local
Attack complexity High
Privileges required High
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

April 7, 2026 CVE published
April 20, 2026 Record updated