CVE-2026-13212

{"id": "CVE-2026-13212", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-13212", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-08-24T20:19:17.728177Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "vulnerabilities@zephyrproject.org", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "ADJACENT_NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.8}]}, "affected": [{"source": "vulnerabilities@zephyrproject.org", "affectedData": [{"vendor": "zephyrproject", "product": "zephyr", "versions": [{"status": "affected", "version": "4.2.0", "lessThan": "4.4.2", "versionType": "semver"}], "packageName": "zephyr", "programFiles": ["drivers/virtio/virtio_common.c"], "collectionURL": "https://github.com/zephyrproject-rtos/zephyr", "defaultStatus": "unaffected"}]}], "published": "2026-08-24T16:16:55.393", "references": [{"url": "https://github.com/zephyrproject-rtos/zephyr/commit/fe47dbca080957c425383cc1d5bdc7d48a41d4a5", "source": "vulnerabilities@zephyrproject.org"}, {"url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-7884-373w-qqhx", "source": "vulnerabilities@zephyrproject.org"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "vulnerabilities@zephyrproject.org", "description": [{"lang": "en", "value": "CWE-129"}]}], "descriptions": [{"lang": "en", "value": "The Zephyr virtio driver does not validate the descriptor-chain head id that the virtio device writes into the used ring. In virtio_isr() (drivers/virtio/virtio_common.c), the device-written vq->used->ring[idx].id is used directly as an index into vq->recv_cbs[] and vq->desc[], which are both allocated with exactly vq->num entries. recv_cbs[] holds {cb, opaque} callback entries, and the indexed callback pointer is then invoked as cbe.cb(cbe.opaque, used_len).\n\nBecause the id is consumed as a 16-bit value with no bound check, a malicious or compromised virtio backend (an untrusted hypervisor, or an untrusted hardware/peer-processor virtio device on a PCI or MMIO transport) can supply an id far beyond vq->num. This causes an out-of-bounds read of a {function pointer, argument} pair from heap memory beyond recv_cbs[], after which the driver calls that attacker-shaped pointer in the guest's interrupt context. No guest privileges or user interaction are required; the backend triggers it by writing the shared used ring and raising the queue interrupt.\n\nThe result is an arbitrary / attacker-influenced function-pointer call in the Zephyr guest, i.e. a control-flow-hijack primitive that can lead to code execution or, at minimum, a reliable crash. The fix rejects any used-ring id >= vq->num before indexing recv_cbs[]/desc[] or invoking the callback. This affects builds using CONFIG_VIRTIO with the PCI or MMIO transport."}, {"lang": "es", "value": "El controlador virtio de Zephyr no valida el ID de cabecera de la cadena de descriptores que el dispositivo virtio escribe en el anillo de usados. En virtio_isr() (drivers/virtio/virtio_common.c), el ID vq -> used -> ring[idx].id escrito por el dispositivo se utiliza directamente como un \u00edndice en vq -> recv_cbs[] y vq -> desc[], los cuales est\u00e1n ambos asignados con exactamente vq -> num entradas. recv_cbs[] contiene entradas de callback {cb, opaque}, y el puntero de callback indexado se invoca entonces como cbe.cb(cbe.opaque, used_len).\n\nDebido a que el ID se consume como un valor de 16 bits sin verificaci\u00f3n de l\u00edmites, un backend virtio malicioso o comprometido (un hipervisor no confiable, o un dispositivo virtio de hardware/procesador par no confiable en un transporte PCI o MMIO) puede suministrar un ID mucho m\u00e1s all\u00e1 de vq -> num. Esto causa una lectura fuera de l\u00edmites de un par {puntero de funci\u00f3n, argumento} de la memoria del heap m\u00e1s all\u00e1 de recv_cbs[], despu\u00e9s de lo cual el controlador llama a ese puntero con forma de atacante en el contexto de interrupci\u00f3n del invitado. No se requieren privilegios de invitado ni interacci\u00f3n del usuario; el backend lo activa escribiendo en el anillo de usados compartido y elevando la interrupci\u00f3n de la cola.\n\nEl resultado es una llamada a puntero de funci\u00f3n arbitraria / influenciada por el atacante en el invitado Zephyr, es decir, una primitiva de secuestro de flujo de control que puede conducir a la ejecuci\u00f3n de c\u00f3digo o, como m\u00ednimo, a un fallo fiable. La soluci\u00f3n rechaza cualquier ID de anillo de usados >= vq -> num antes de indexar recv_cbs[]/desc[] o invocar el callback. Esto afecta a las compilaciones que utilizan CONFIG_VIRTIO con el transporte PCI o MMIO."}], "lastModified": "2026-10-12T15:10:00.207", "sourceIdentifier": "vulnerabilities@zephyrproject.org"}