{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-40051", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.157Z", "datePublished": "2025-10-28T11:48:27.279Z", "dateUpdated": "2026-08-05T12:07:22.761Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:07:22.761Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvhost: vringh: Modify the return value check\n\nThe return value of copy_from_iter and copy_to_iter can't be negative,\ncheck whether the copied lengths are equal." } ], "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 vulnerable vringh IOTLB copy path is driven entirely through local ioctls on the `/dev/vhost-vdpa-N` character device (VHOST_IOTLB_UPDATE, vring setup, kick), with no network-facing consumer. A malicious guest cannot trigger it because it cannot unmap the host-side VA backing, so the attacker must be a local process.\nAC:L - The attacker deterministically forces the short copy by registering an IOTLB mapping over a shared file mapping and then truncating/unmapping it, so `copy_from_user` faults at a chosen offset every time — no race or unpredictable state is involved. The stale-stack values feeding `hdr.sector` and `struct vring_desc` are groomable with ordinary syscalls.\nPR:L - `vhost_vdpa_open()` and the vhost-vdpa ioctl handlers contain no `capable()`/`CAP_*` checks, so any user holding the device node can drive the full path, and in standard virtualization deployments that node is granted to an unprivileged VMM process. Only device *creation* needs admin, which is the normal host configuration, not an attacker step.\nUI:N - The attacker performs every step itself — map, truncate, kick the virtqueue — within its own process. No victim action or interaction is required.\nS:U - The corruption and disclosure occur in the host kernel that already governs the attacking process; this is standard local kernel compromise. No IOMMU, VM, or sandbox authority boundary is crossed by the bug itself.\nC:H - A silently-swallowed short pull causes `vdpasim_net_work()` to push a full PAGE_SIZE of the non-zeroed `kvmalloc` buffer `net->buffer` into the attacker's RX ring, directly disclosing stale kernel heap. Additionally the uninitialized `hdr.sector` drives `vringh_iov_push_iotlb(..., blk->buffer + offset, ...)` past the wrapped `VDPASIM_BLK_CAPACITY - start_sector` guard, giving an out-of-bounds kernel heap read echoed back to the attacker.\nI:H - In `vdpasim_blk_handle_req()` the uninitialized stack `hdr.sector` becomes the destination offset for `vringh_iov_pull_iotlb(..., blk->buffer + (sector << SECTOR_SHIFT), to_pull)`, an out-of-bounds kernel heap write of attacker-supplied data at a groomable offset. `__vringh_iov()` likewise builds iov entries whose `iov_base`/`iov_len` come from uninitialized kernel stack, giving further attacker-influenced memory corruption.\nA:H - Descriptors and request headers fabricated from uninitialized kernel stack yield bogus IOVAs and lengths up to 4 GB, and the resulting out-of-bounds heap accesses and invalid `pfn_to_page()`/page translations cause kernel oops or panic. The condition is repeatable at will from a single unprivileged process." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/vhost/vringh.c" ], "versions": [ { "version": "309bba39c945ac8ab8083ac05cd6cfe5822968e0", "lessThan": "db042925a5ab7a550b710addeadbf6f72e3a8a4b", "status": "affected", "versionType": "git" }, { "version": "309bba39c945ac8ab8083ac05cd6cfe5822968e0", "lessThan": "78dc7362662fedaa1928fb8e4f27401c8322905d", "status": "affected", "versionType": "git" }, { "version": "309bba39c945ac8ab8083ac05cd6cfe5822968e0", "lessThan": "baa37b1c7e29546f79c39bef0d18c4edc9f39bb1", "status": "affected", "versionType": "git" }, { "version": "309bba39c945ac8ab8083ac05cd6cfe5822968e0", "lessThan": "cfa0654402c06d086201a9ff167eb95da5844fc3", "status": "affected", "versionType": "git" }, { "version": "309bba39c945ac8ab8083ac05cd6cfe5822968e0", "lessThan": "82a8d0fda55b35361ee7f35b54fa2b66d7847d2b", "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/vringh.c" ], "versions": [ { "version": "6.0", "status": "affected" }, { "version": "0", "lessThan": "6.0", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.156", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.112", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.53", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.3", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18", "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": "6.0", "versionEndExcluding": "6.1.156" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.6.112" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.12.53" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.17.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.18" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/db042925a5ab7a550b710addeadbf6f72e3a8a4b" }, { "url": "https://git.kernel.org/stable/c/78dc7362662fedaa1928fb8e4f27401c8322905d" }, { "url": "https://git.kernel.org/stable/c/baa37b1c7e29546f79c39bef0d18c4edc9f39bb1" }, { "url": "https://git.kernel.org/stable/c/cfa0654402c06d086201a9ff167eb95da5844fc3" }, { "url": "https://git.kernel.org/stable/c/82a8d0fda55b35361ee7f35b54fa2b66d7847d2b" } ], "title": "vhost: vringh: Modify the return value check", "x_generator": { "engine": "bippy-1.2.0" } } } }