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.
"}],"value":"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.\n\nTo remediate this, users should upgrade to Firecracker 1.14.4 or 1.15.1 and later."}],"impacts":[{"capecId":"CAPEC-100","descriptions":[{"lang":"en","value":"CAPEC-100 Overflow Buffers"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"LOCAL","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"HIGH","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]},{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"HIGH","attackRequirements":"PRESENT","attackVector":"LOCAL","baseScore":8.7,"baseSeverity":"HIGH","exploitMaturity":"NOT_DEFINED","privilegesRequired":"HIGH","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"HIGH","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H","version":"4.0","vulnAvailabilityImpact":"HIGH","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-787","description":"CWE-787 Out-of-bounds write","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-369","description":"CWE-369 Divide by zero","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-04-20T15:47:54.142Z","orgId":"ff89ba41-3aa1-4d27-914a-91399e9639e5","shortName":"AMZN"},"references":[{"tags":["patch"],"url":"https://github.com/firecracker-microvm/firecracker/releases/tag/v1.15.1"},{"tags":["patch"],"url":"https://github.com/firecracker-microvm/firecracker/releases/tag/v1.14.4"},{"tags":["vendor-advisory"],"url":"https://aws.amazon.com/security/security-bulletins/2026-015-aws/"},{"tags":["third-party-advisory"],"url":"https://github.com/firecracker-microvm/firecracker/security/advisories/GHSA-776c-mpj7-jm3r"}],"source":{"discovery":"UNKNOWN"},"title":"Out-of-bounds Write in Firecracker virtio-pci Transport","x_generator":{"engine":"Vulnogram 1.0.1"}}},"cveMetadata":{"assignerOrgId":"ff89ba41-3aa1-4d27-914a-91399e9639e5","assignerShortName":"AMZN","cveId":"CVE-2026-5747","datePublished":"2026-04-07T23:17:23.944Z","dateReserved":"2026-04-07T14:39:46.309Z","dateUpdated":"2026-04-20T15:47:54.142Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-04-08 00:16:05","lastModifiedDate":"2026-04-20 16:16:49","problem_types":["CWE-369","CWE-787","CWE-787 CWE-787 Out-of-bounds write","CWE-369 CWE-369 Divide by zero"],"metrics":{"cvssMetricV40":[{"source":"ff89ba41-3aa1-4d27-914a-91399e9639e5","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":8.7,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"HIGH","attackRequirements":"PRESENT","privilegesRequired":"HIGH","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"HIGH","subIntegrityImpact":"HIGH","subAvailabilityImpact":"HIGH","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"ff89ba41-3aa1-4d27-914a-91399e9639e5","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"HIGH","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":0.8,"impactScore":6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"5747","Ordinal":"1","Title":"Out-of-bounds Write in Firecracker virtio-pci Transport","CVE":"CVE-2026-5747","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"5747","Ordinal":"1","NoteData":"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.\n\nTo remediate this, users should upgrade to Firecracker 1.14.4 or 1.15.1 and later.","Type":"Description","Title":"Out-of-bounds Write in Firecracker virtio-pci Transport"}]}}}