CVE-2026-5747: Out-of-bounds Write in Firecracker virtio-pci Transport
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 x8664 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 Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Firecrackerto a version that resolves this vulnerability.Fixed in 1.14.4 - Upgrade
Upgrade
Firecrackerto a version that resolves this vulnerability.Fixed in 1.15.1
Event History
Frequently Asked Questions
What is the severity of CVE-2026-5747?
CVE-2026-5747 is considered a high severity vulnerability due to its potential to crash the Firecracker VMM process or allow escalation of privileges.
How do I fix CVE-2026-5747?
To fix CVE-2026-5747, upgrade Amazon Firecracker to version 1.15.1 or later, or to version 1.14.4 or later.
Which versions of Amazon Firecracker are affected by CVE-2026-5747?
Amazon Firecracker versions 1.13.0 through 1.14.3 and version 1.15.0 are affected by CVE-2026-5747.
Can CVE-2026-5747 be exploited remotely?
CVE-2026-5747 requires local guest user access with root privileges to be exploited.
What is the impact of CVE-2026-5747 on Firecracker users?
The impact of CVE-2026-5747 includes system instability and the potential for unauthorized code execution.