{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64259", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.773Z", "datePublished": "2026-07-25T08:49:10.756Z", "dateUpdated": "2026-08-17T04:52:12.445Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:52:12.445Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfuse-uring: make a fuse_req on SQE commit only findable after memcpy\n\nBad userspace might try to trick us and send commit SQEs request\nunique / commit-id of requests that are not even send to\nfuse-server (io_uring_cmd_done() not called) yet.\n\nfuse_uring_commit_fetch() ends the fuse request when the ring entry\nhas a wrong state, but that could have caused a use-after-free\nwith the memcpy operations in fuse_uring_send_in_task().\nIn order to avoid such races the call of fuse_uring_add_to_pq()\nis moved after the copy operations and just before completing\nthe io-uring request - malicious userspace cannot find the request\nanymore until all prepration work in fuse-client/kernel is completed.\n\nThis also moves fuse_uring_add_to_pq() a bit up in the code to\navoid a forward declaration. Also not with a preparation commit,\nto make it easier to back port to older kernels."}], "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 - Triggering requires local filesystem operations and IORING_OP_URING_CMD submissions on an associated /dev/fuse descriptor. Network peers cannot directly reach this commit path.\nAC:L - The attacker controls request generation, predictable sequential commit IDs, concurrent commit submission, and deferred io_uring task-work execution. Both sides of the race are attacker-controlled.\nPR:L - An ordinary user can create and operate a FUSE mount through fusermount or CAP_SYS_ADMIN in a user namespace; FUSE permits user-namespace mounts and this path has no init-namespace capability check.\nUI:N - The attacker can operate both the FUSE daemon and a client thread that generates requests, requiring no victim action.\nS:U - Exploitation compromises the host kernel within the same security authority and does not cross a VM, IOMMU, or comparable boundary.\nC:H - The freed request's argument pointers and copy sources are dereferenced while copying into attacker-controlled ring memory. Heap reclamation can therefore expose sensitive kernel memory.\nI:H - The use-after-free performs writes to reclaimed request memory through embedded spinlocks and request flags, providing exploitable heap corruption that may enable arbitrary writes or kernel code execution.\nA:H - The dangling request can cause invalid dereferences, corrupted request state, double completion, hangs, or a kernel panic."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/fuse/dev_uring.c"], "versions": [{"version": "c090c8abae4b6b77a1bee116aa6c385456ebef96", "lessThan": "e1711479e9068ea31b31353a702a51e639c3d059", "status": "affected", "versionType": "git"}, {"version": "c090c8abae4b6b77a1bee116aa6c385456ebef96", "lessThan": "a635f427d57e2012102ae4886b48d8955c59fb86", "status": "affected", "versionType": "git"}, {"version": "c090c8abae4b6b77a1bee116aa6c385456ebef96", "lessThan": "1efd3d474fc0ba74dfd984249bca78807d739812", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/fuse/dev_uring.c"], "versions": [{"version": "6.14", "status": "affected"}, {"version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.39", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.4", "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": "6.14", "versionEndExcluding": "6.18.39"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.1.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/e1711479e9068ea31b31353a702a51e639c3d059"}, {"url": "https://git.kernel.org/stable/c/a635f427d57e2012102ae4886b48d8955c59fb86"}, {"url": "https://git.kernel.org/stable/c/1efd3d474fc0ba74dfd984249bca78807d739812"}], "title": "fuse-uring: make a fuse_req on SQE commit only findable after memcpy", "x_generator": {"engine": "bippy-1.2.0"}}}}