{"id":"CVE-2026-74312","state":"PUBLISHED","title":"vhost/vdpa: validate virtqueue index in mmap and fault paths","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nvhost/vdpa: validate virtqueue index in mmap and fault paths\n\nvhost_vdpa_mmap() and vhost_vdpa_fault() use vma->vm_pgoff as a\nvirtqueue index for get_vq_notification(), but they do not validate\nthat the index is smaller than v->nvqs.\n\nThe ioctl path already performs both a bounds check and\narray_index_nospec(), but the mmap/fault path only checks that the\nindex fits in u16. This allows an out-of-range queue index to reach\ndriver-specific get_vq_notification() callbacks.\n\nFix this by extracting a unified vhost_vdpa_get_vq_notification()\nhelper that validates the queue index against v->nvqs and applies\narray_index_nospec() before calling the driver callback. Both the\nmmap and fault paths use this helper, and the bounds checking is\nconsolidated into a single location.\n\nFrom source inspection, the most defensible impact is out-of-bounds\naccess in the callback path, potentially leading to invalid PFN\nremaps and crash/DoS.","publishedAt":"2026-08-15T05:58:11.395Z","updatedAt":"2026-10-16T18:55:32.188Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"0f310bac6db9bd3bb1655707d692d9d2a86eeb17","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"4bf5a51963ff816f7443702dc536b9327cf5e550","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"55a644031e610ea93fbde2702c7b8f267476552f","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"2b3f79b90b231a682315fe2191bb71925650e183","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"bbba4f92515238d76018e9b75e41b16d83df52c8","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"1f5f94c6c6b2e4eaa5b45815509e21d0c6cfa81e","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"32ac9097aa2463fcfc12f61cc4a9ebc3579cba7d","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"929e4f044621c8cc30b612fb74e1410bef09e41b","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/vhost/vdpa.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.8","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/vhost/vdpa.c"]}],"references":["https://git.kernel.org/stable/c/0f310bac6db9bd3bb1655707d692d9d2a86eeb17","https://git.kernel.org/stable/c/4bf5a51963ff816f7443702dc536b9327cf5e550","https://git.kernel.org/stable/c/55a644031e610ea93fbde2702c7b8f267476552f","https://git.kernel.org/stable/c/2b3f79b90b231a682315fe2191bb71925650e183","https://git.kernel.org/stable/c/bbba4f92515238d76018e9b75e41b16d83df52c8","https://git.kernel.org/stable/c/1f5f94c6c6b2e4eaa5b45815509e21d0c6cfa81e","https://git.kernel.org/stable/c/32ac9097aa2463fcfc12f61cc4a9ebc3579cba7d","https://git.kernel.org/stable/c/929e4f044621c8cc30b612fb74e1410bef09e41b"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74312.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74312","state":"PUBLISHED","datePublished":"2026-08-15T05:58:11.395Z","dateUpdated":"2026-10-16T18:55:32.188Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.883Z"},"containers":{"cna":{"title":"vhost/vdpa: validate virtqueue index in mmap and fault paths","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nvhost/vdpa: validate virtqueue index in mmap and fault paths\n\nvhost_vdpa_mmap() and vhost_vdpa_fault() use vma->vm_pgoff as a\nvirtqueue index for get_vq_notification(), but they do not validate\nthat the index is smaller than v->nvqs.\n\nThe ioctl path already performs both a bounds check and\narray_index_nospec(), but the mmap/fault path only checks that the\nindex fits in u16. This allows an out-of-range queue index to reach\ndriver-specific get_vq_notification() callbacks.\n\nFix this by extracting a unified vhost_vdpa_get_vq_notification()\nhelper that validates the queue index against v->nvqs and applies\narray_index_nospec() before calling the driver callback. Both the\nmmap and fault paths use this helper, and the bounds checking is\nconsolidated into a single location.\n\nFrom source inspection, the most defensible impact is out-of-bounds\naccess in the callback path, potentially leading to invalid PFN\nremaps and crash/DoS."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"0f310bac6db9bd3bb1655707d692d9d2a86eeb17","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"4bf5a51963ff816f7443702dc536b9327cf5e550","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"55a644031e610ea93fbde2702c7b8f267476552f","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"2b3f79b90b231a682315fe2191bb71925650e183","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"bbba4f92515238d76018e9b75e41b16d83df52c8","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"1f5f94c6c6b2e4eaa5b45815509e21d0c6cfa81e","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"32ac9097aa2463fcfc12f61cc4a9ebc3579cba7d","versionType":"git"},{"version":"ddd89d0a059d8e9740c75a97e0efe9bf07ee51f9","status":"affected","lessThan":"929e4f044621c8cc30b612fb74e1410bef09e41b","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/vhost/vdpa.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.8","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.8","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/vhost/vdpa.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/0f310bac6db9bd3bb1655707d692d9d2a86eeb17"},{"url":"https://git.kernel.org/stable/c/4bf5a51963ff816f7443702dc536b9327cf5e550"},{"url":"https://git.kernel.org/stable/c/55a644031e610ea93fbde2702c7b8f267476552f"},{"url":"https://git.kernel.org/stable/c/2b3f79b90b231a682315fe2191bb71925650e183"},{"url":"https://git.kernel.org/stable/c/bbba4f92515238d76018e9b75e41b16d83df52c8"},{"url":"https://git.kernel.org/stable/c/1f5f94c6c6b2e4eaa5b45815509e21d0c6cfa81e"},{"url":"https://git.kernel.org/stable/c/32ac9097aa2463fcfc12f61cc4a9ebc3579cba7d"},{"url":"https://git.kernel.org/stable/c/929e4f044621c8cc30b612fb74e1410bef09e41b"}],"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 flaw is reached only via local mmap()/page-fault handling on /dev/vhost-vdpa-N (vma->vm_pgoff selects the virtqueue); there is no network, adjacent-radio, or physical-device path to this code.\nAC:L - Once the device node is open, the attacker fully controls vm_pgoff and can pick any index up to 65535; no race, rare config, or victim-dependent timing is required to hit the out-of-range callback.\nPR:L - vhost_vdpa_open()/mmap() perform no capable() checks; in typical cloud/hypervisor deployments the vhost-vdpa char device is held by an unprivileged VMM/QEMU account (or a compromised QEMU), not init-namespace root.\nUI:N - Exploitation requires only the attacker's own open/mmap of the vhost-vdpa device with a crafted pgoff; no separate victim mount, click, or administrative action is needed.\nS:U - Impact stays within the host kernel security domain reached through the vhost-vdpa interface; it is not a guest-to-host VM escape or IOMMU-boundary bypass by itself.\nC:H - An out-of-range index drives driver get_vq_notification() callbacks (e.g. vp_vdpa/ifcvf/pds/octeon) to read past vring metadata; the returned notify.addr is then used by vmf_insert_pfn(), enabling arbitrary physical-page mapping and kernel memory disclosure.\nI:H - The mmap mapping is write-only doorbell access; remapping an attacker-chosen physical page via the corrupted notify.addr grants a write primitive to arbitrary physical memory and device MMIO, supporting control-flow or privilege manipulation.\nA:H - Invalid or attacker-influenced PFN insertion during fault handling can BUG/oops the kernel immediately; even without full exploitation, the out-of-bounds callback access provides a reliable host crash/DoS vector."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:45:44.929Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"5.10.261"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"5.15.212"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.8","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-74312","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T18:53:00.610908Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T18:55:32.188Z"}}]}}}