CVE-2026-64211

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{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/rcu/srcutree.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a4153538fcd2361c4e0039eb103265492d26044e", "status": "affected", "version": "61bbcfb50514a8a94e035a7349697a3790ab4783", "versionType": "git"}, {"lessThan": "593889c401426004bd0ea0f6d4fcece728b03420", "status": "affected", "version": "61bbcfb50514a8a94e035a7349697a3790ab4783", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/rcu/srcutree.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.0"}, {"lessThan": "7.0", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "7.0.*", "status": "unaffected", "version": "7.0.11", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "3599D100-DF0E-4F7B-90E5-56ECF94051B8", "versionEndExcluding": "7.0.11", "versionStartIncluding": "7.0.1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:-:*:*:*:*:*:*", "matchCriteriaId": "EF897730-3F1E-47A2-8B07-22535202C487", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*", "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*", "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*", "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*", "matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*", "matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsrcu: Don't queue workqueue handlers to never-online CPUs\n\nWhile an srcu_struct structure is in the midst of switching from CPU-0\nto all-CPUs state, it can attempt to invoke callbacks for CPUs that\nhave never been online. Worse yet, it can attempt in invoke callbacks\nfor CPUs that never will be online, even including imaginary CPUs not in\ncpu_possible_mask. This can cause hangs on s390, which is not set up to\ndeal with workqueue handlers being scheduled on such CPUs. This commit\ntherefore causes Tree SRCU to refrain from queueing workqueue handlers\non CPUs that have not yet (and might never) come online.\n\nBecause callbacks are not invoked on CPUs that have not been\nonline, it is an error to invoke call_srcu(), synchronize_srcu(), or\nsynchronize_srcu_expedited() on a CPU that is not yet fully online.\nHowever, it turns out to be less code to redirect the callbacks\nfrom too-early invocations of call_srcu() than to warn about such\ninvocations. This commit therefore also redirects callbacks queued on\nnot-yet-fully-online CPUs to the boot CPU."}], "id": "CVE-2026-64211", "lastModified": "2026-08-11T17:24:10.577", "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": "2026-07-24T16:16:48.747", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/593889c401426004bd0ea0f6d4fcece728b03420"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a4153538fcd2361c4e0039eb103265492d26044e"}], "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: srcu: Don't queue workqueue handlers to never-online CPUs", "id": "2506809", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2506809"}, "csaw": false, "cwe": "CWE-821", "details": ["A flaw was found in the Linux kernel. During certain CPU state transitions, the kernel's srcu_struct mechanism may attempt to schedule tasks on processors that are not active or will never be online. This incorrect scheduling of workqueue handlers can lead to system unresponsiveness, specifically causing hangs on s390 architectures. This vulnerability could result in a denial of service, making the system unavailable."], "name": "CVE-2026-64211", "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": "2026-07-24T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64211\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64211\nhttps://lore.kernel.org/linux-cve-announce/2026072414-CVE-2026-64211-f6d4@gregkh/T"]}

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