{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74306", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.883Z", "datePublished": "2026-08-15T05:58:07.313Z", "dateUpdated": "2026-08-17T05:45:40.501Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:45:40.501Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/qat: fix f_pos race in qat_vf_resume_write()\n\nqat_vf_resume_write() checks filp->f_pos before taking migf->lock, but\ncopies into the migration-state buffer after taking the lock and\nre-reading the shared file position.\n\nTwo concurrent writers could therefore pass the bounds check with the\nold offset, then have the second writer copy after the first advanced\nf_pos, writing past the end of the migration-state buffer.\n\nTake migf->lock before doing the boundary checks." } ], "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 - Exploitation requires local write() syscalls on a VFIO live-migration resume fd returned by VFIO_DEVICE_FEATURE_MIG_DEVICE_STATE ioctl on an opened QAT VFIO PCI device; there is no network, adjacent-wireless, or physical-device attack path to this code.\nAC:L - An attacker with the migration fd controls both racing writers (e.g., concurrent threads or dup'd fds sharing f_pos) and can repeatedly trigger the TOCTOU window near the buffer end until the overflow succeeds; no uncontrollable victim timing or memory layout is required.\nPR:L - Exploitation requires only local access to an assigned Intel QAT VFIO device migration fd (typical QEMU/cloud/HPC VFIO clients), not real root in the init namespace; capabilities like CAP_NET_ADMIN via user namespaces do not grant this path.\nUI:N - No victim interaction is required; the attacker drives VFIO migration state transitions and concurrent writes to the resume fd programmatically without any separate user or administrator action during exploitation.\nS:U - The flaw corrupts host kernel heap memory from a VFIO client context and does not by itself cross an IOMMU, VM-guest, or other distinct security authority boundary; impact remains host kernel compromise/DoS within the same authority.\nC:H - The race yields an attacker-controlled heap out-of-bounds write past the 4096-byte migration-state kmalloc buffer, which can corrupt adjacent kernel objects and be leveraged for arbitrary kernel memory disclosure, not merely a bounded leak.\nI:H - copy_from_user() writes attacker-controlled data beyond mig_dev->state, enabling heap corruption and potential arbitrary kernel write or code-execution primitives through grooming of adjacent kmalloc objects.\nA:H - Heap corruption from the out-of-bounds write can immediately panic or oops the kernel or destabilize the system even when full exploitation is not attempted, satisfying high availability impact for kernel memory corruption." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/vfio/pci/qat/main.c" ], "versions": [ { "version": "bb208810b1abf1c84870cfbe1cc9cf1a1d35c607", "lessThan": "6465af0004dc1b067129a26ef44f19cdf13bbce6", "status": "affected", "versionType": "git" }, { "version": "bb208810b1abf1c84870cfbe1cc9cf1a1d35c607", "lessThan": "d416dcefdbac90d96b22485fd93f28229ad9984b", "status": "affected", "versionType": "git" }, { "version": "bb208810b1abf1c84870cfbe1cc9cf1a1d35c607", "lessThan": "b6fd7a40a66485c8aa8156d8fcf50b95cb8ba281", "status": "affected", "versionType": "git" }, { "version": "bb208810b1abf1c84870cfbe1cc9cf1a1d35c607", "lessThan": "4ec5e932e636896e97e4c6a8205b0ac76d52421a", "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/vfio/pci/qat/main.c" ], "versions": [ { "version": "6.10", "status": "affected" }, { "version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "6.10", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/6465af0004dc1b067129a26ef44f19cdf13bbce6" }, { "url": "https://git.kernel.org/stable/c/d416dcefdbac90d96b22485fd93f28229ad9984b" }, { "url": "https://git.kernel.org/stable/c/b6fd7a40a66485c8aa8156d8fcf50b95cb8ba281" }, { "url": "https://git.kernel.org/stable/c/4ec5e932e636896e97e4c6a8205b0ac76d52421a" } ], "title": "vfio/qat: fix f_pos race in qat_vf_resume_write()", "x_generator": { "engine": "bippy-1.2.0" } } } }