CVE-2026-64263

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{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/fuse/dev_uring.c", "fs/fuse/dev_uring_i.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "50f3e03db823cabc41fe35c27d77c2bdb112baad", "status": "affected", "version": "4fea593e625cd50d4d11be227007849b12f17bfb", "versionType": "git"}, {"lessThan": "e8afc85acdf329361b2d8df2ad9b52364686235f", "status": "affected", "version": "4fea593e625cd50d4d11be227007849b12f17bfb", "versionType": "git"}, {"lessThan": "198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc", "status": "affected", "version": "4fea593e625cd50d4d11be227007849b12f17bfb", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/fuse/dev_uring.c", "fs/fuse/dev_uring_i.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.16"}, {"lessThan": "6.16", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.39", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "FFBD7467-7FB0-4538-9CC0-98199E9EC402", "versionEndExcluding": "6.18.39", "versionStartIncluding": "6.16", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42", "versionEndExcluding": "7.1.4", "versionStartIncluding": "6.19", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "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."}], "id": "CVE-2026-64263", "lastModified": "2026-08-17T05:17:25.063", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-07-25T10:17:06.460", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/50f3e03db823cabc41fe35c27d77c2bdb112baad"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e8afc85acdf329361b2d8df2ad9b52364686235f"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"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"]}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4fea593e625cd50d4d11be227007849b12f17bfb,50f3e03db823cabc41fe35c27d77c2bdb112baad)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4fea593e625cd50d4d11be227007849b12f17bfb,e8afc85acdf329361b2d8df2ad9b52364686235f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4fea593e625cd50d4d11be227007849b12f17bfb,198f45eeb9f78b2a2d6d8be95e4e43468eb2c6bc)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.16"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.16)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.39,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.4,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-07-25T11:15:04.068074+00:00", "updated": "2026-08-13T10:30:04.819857+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}