CVE-2026-5747
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.21%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.21% probability · 11th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-369, CWE-787
- Affected
- amazon/firecracker
- Source
- ff89ba41-3aa1-4d27-914a-91399e9639e5
References
- https://aws.amazon.com/security/security-bulletins/2026-015-aws/Vendor Advisory
- https://github.com/firecracker-microvm/firecracker/releases/tag/v1.14.4Release Notes
- https://github.com/firecracker-microvm/firecracker/releases/tag/v1.15.1Release Notes
- https://github.com/firecracker-microvm/firecracker/security/advisories/GHSA-776c-mpj7-jm3rVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.