{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64263", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.774Z", "datePublished": "2026-07-25T08:49:13.217Z", "dateUpdated": "2026-08-17T04:52:16.831Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:52:16.831Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfuse-uring: fix moving cancelled entry to ent_in_userspace list\n\nfuse_uring_cancel() moves entries that are available (these have no reqs\nattached) to the ent_in_userspace list. ent_list_request_expired()\nchecks the first entry on ent_in_userspace and dereferences\nent->fuse_req unconditionally, which will crash on a cancelled entry\nthat was moved to this list.\n\nFix this by freeing the entry and dropping queue_refs directly in\nfuse_uring_cancel(). This is safe because cancel is the cancel handler\nitself - after io_uring_cmd_done(), no more cancels will be dispatched\nfor this command, and teardown serializes with cancel via queue->lock.\n\nSince cancel now decrements queue_refs, fuse_uring_abort() must no\nlonger gate fuse_uring_abort_end_requests() on queue_refs > 0, as\ncancelled entries may have already dropped queue_refs while requests are\nstill queued. Remove the gate so abort always flushes requests and stops\nqueues."}], "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", "fs/fuse/dev_uring_i.h"], "versions": [{"version": "4fea593e625cd50d4d11be227007849b12f17bfb", "lessThan": "50f3e03db823cabc41fe35c27d77c2bdb112baad", "status": "affected", "versionType": "git"}, {"version": "4fea593e625cd50d4d11be227007849b12f17bfb", "lessThan": "e8afc85acdf329361b2d8df2ad9b52364686235f", "status": "affected", "versionType": "git"}, {"version": "4fea593e625cd50d4d11be227007849b12f17bfb", "lessThan": "198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc", "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", "fs/fuse/dev_uring_i.h"], "versions": [{"version": "6.16", "status": "affected"}, {"version": "0", "lessThan": "6.16", "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": "6.16", "versionEndExcluding": "6.18.39"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "7.1.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/50f3e03db823cabc41fe35c27d77c2bdb112baad"}, {"url": "https://git.kernel.org/stable/c/e8afc85acdf329361b2d8df2ad9b52364686235f"}, {"url": "https://git.kernel.org/stable/c/198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc"}], "title": "fuse-uring: fix moving cancelled entry to ent_in_userspace list", "x_generator": {"engine": "bippy-1.2.0"}}}}

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{"bugzilla": {"description": "kernel: fuse-uring: fix moving cancelled entry to ent_in_userspace list", "id": "2507179", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2507179"}, "csaw": false, "cwe": "CWE-476", "details": ["A flaw was found in the Linux kernel's fuse-uring component. This vulnerability arises from the incorrect handling of cancelled entries, which are moved to a list where a subsequent operation unconditionally attempts to access a null pointer. A local attacker could exploit this flaw to trigger a system crash, leading to a Denial of Service (DoS)."], "name": "CVE-2026-64263", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-07-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64263\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64263\nhttps://lore.kernel.org/linux-cve-announce/2026072558-CVE-2026-64263-971f@gregkh/T"]}