{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2021-46967", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-02-27T18:42:55.943Z", "datePublished": "2024-02-27T18:47:04.253Z", "dateUpdated": "2026-08-05T08:45:17.104Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:45:17.104Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvhost-vdpa: fix vm_flags for virtqueue doorbell mapping\n\nThe virtqueue doorbell is usually implemented via registeres but we\ndon't provide the necessary vma->flags like VM_PFNMAP. This may cause\nseveral issues e.g when userspace tries to map the doorbell via vhost\nIOTLB, kernel may panic due to the page is not backed by page\nstructure. This patch fixes this by setting the necessary\nvm_flags. With this patch, try to map doorbell via IOTLB will fail\nwith bad address." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is reached only via local open/mmap/ioctl on `/dev/vhost-vdpa-N` (mmap of the virtqueue doorbell, then a vhost IOTLB update on that uaddr), not via network packets or adjacent-link protocols.\nAC:L - An attacker who can open the device can deterministically mmap the doorbell and submit a VHOST_IOTLB_UPDATE for that address without depending on races, special memory layout, or other conditions outside their control.\nPR:L - There is no capability check on the open/mmap/IOTLB path; access is gated only by DAC on the vhost-vdpa node, which in standard libvirt/QEMU deployments is held by an unprivileged VMM account (same model as CVE-2024-47748).\nUI:N - The attacker performs the mmap and IOTLB update from their own process; no separate victim action is required.\nS:U - Impact is confined to the host kernel authority that already owns the vhost-vdpa/IOTLB path; this is not a guest-to-host escape or an exploit whose defining effect is crossing an IOMMU/VM boundary.\nC:H - Without VM_PFNMAP, IOTLB pinning of the doorbell can proceed into GUP’s PFNMAP -EEXIST path, which in the affected kernels left page_list entries unset so page_to_pfn/IOMMU map operate on attacker-influenced garbage, enabling arbitrary physical-memory disclosure via bad DMA maps.\nI:H - The same uninitialized-page / wrong-PFN IOTLB install and later pfn_to_page/unpin_user_page teardown provide kernel memory corruption and arbitrary DMA write primitives against host physical memory.\nA:H - The fix explicitly documents that mapping the doorbell via vhost IOTLB can panic the kernel because the page is not backed by a struct page, which is High availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/vhost/vdpa.c" ], "versions": [ { "version": "ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9", "lessThan": "3b8b6399666a29daa30b0bb3f5c9e3fc81c5a6a6", "status": "affected", "versionType": "git" }, { "version": "ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9", "lessThan": "940230a5c31e2714722aee04c521a21f484b4df7", "status": "affected", "versionType": "git" }, { "version": "ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9", "lessThan": "93dbbf20e3ffad14f04227a0b7105f6e6f0387ce", "status": "affected", "versionType": "git" }, { "version": "ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9", "lessThan": "3a3e0fad16d40a2aa68ddf7eea4acdf48b22dd44", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/vhost/vdpa.c" ], "versions": [ { "version": "5.8", "status": "affected" }, { "version": "0", "lessThan": "5.8", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.36", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.11.20", "lessThanOrEqual": "5.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.12.3", "lessThanOrEqual": "5.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.13", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "5.10.36" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "5.11.20" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "5.12.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.8", "versionEndExcluding": "5.13" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3b8b6399666a29daa30b0bb3f5c9e3fc81c5a6a6" }, { "url": "https://git.kernel.org/stable/c/940230a5c31e2714722aee04c521a21f484b4df7" }, { "url": "https://git.kernel.org/stable/c/93dbbf20e3ffad14f04227a0b7105f6e6f0387ce" }, { "url": "https://git.kernel.org/stable/c/3a3e0fad16d40a2aa68ddf7eea4acdf48b22dd44" } ], "title": "vhost-vdpa: fix vm_flags for virtqueue doorbell mapping", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CISA ADP Vulnrichment", "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2021-46967", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-02-27T19:32:37.039372Z" } } } ], "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-06-04T17:13:04.232Z" } }, { "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:17:43.025Z" }, "title": "CVE Program Container", "references": [ { "url": "https://git.kernel.org/stable/c/3b8b6399666a29daa30b0bb3f5c9e3fc81c5a6a6", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/940230a5c31e2714722aee04c521a21f484b4df7", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/93dbbf20e3ffad14f04227a0b7105f6e6f0387ce", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/3a3e0fad16d40a2aa68ddf7eea4acdf48b22dd44", "tags": [ "x_transferred" ] } ] } ] } }