{"api_version":"1","generated_at":"2026-07-26T14:10:00+00:00","cve":"CVE-2026-64477","urls":{"html":"https://cve.report/CVE-2026-64477","api":"https://cve.report/api/cve/CVE-2026-64477.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64477","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64477"},"summary":{"title":"x86,fs/resctrl: Prevent out-of-bounds access while offlining CPU when SNC enabled","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86,fs/resctrl: Prevent out-of-bounds access while offlining CPU when SNC enabled\n\nThe architecture updates the cpu_mask in a domain's header to track which\nonline CPUs are associated with the domain. When this mask becomes empty\nthe architecture initiates offline of the domain that includes calling\non resctrl fs to offline the domain. If it is a monitoring domain in\nwhich LLC occupancy is tracked resctrl fs forces the limbo handler to\nclear all busy RMID state associated with the domain.\n\nThe limbo handler always reads the current event value associated with a\nbusy RMID irrespective of it being checked as part of regular \"is it still\nbusy\" check or whether it will be forced released anyway. When reading an\nRMID on a system with SNC enabled the \"logical RMID\" is converted to the\n\"physical RMID\" and this conversion requires the NUMA node ID of the\nresctrl monitoring domain that is in turn determined by querying the NUMA\nnode ID of any CPU belonging to the monitoring domain.\n\nWhen the monitoring domain is going offline its cpu_mask is empty causing\nthe NUMA node ID query via cpu_to_node() to be done with \"nr_cpu_ids\" as\nargument resulting in an out-of-bounds access.\n\nRefactor the limbo handler to skip reading the RMID when the RMID will\njust be forced to no longer be dirty in the domain anyway. Add a safety\ncheck to the architecture's RMID reader to protect against this scenario.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-25 10:17:33","updated_at":"2026-07-25 10:17:33"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/ebc300b7ee0c669fa76a7a8858298ff32e296103","name":"https://git.kernel.org/stable/c/ebc300b7ee0c669fa76a7a8858298ff32e296103","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/fc16126cc11d9f507130bf84ab137ee0938c900e","name":"https://git.kernel.org/stable/c/fc16126cc11d9f507130bf84ab137ee0938c900e","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/58c5ec23b1a238eb75cb0aba6f69d8f9e68ef0b2","name":"https://git.kernel.org/stable/c/58c5ec23b1a238eb75cb0aba6f69d8f9e68ef0b2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/be1567992417dc92133e74126de7a6066c825ac9","name":"https://git.kernel.org/stable/c/be1567992417dc92133e74126de7a6066c825ac9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64477","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64477","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e13db55b5a0d447dea63cde772c1078405bbbf96 ebc300b7ee0c669fa76a7a8858298ff32e296103 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e13db55b5a0d447dea63cde772c1078405bbbf96 be1567992417dc92133e74126de7a6066c825ac9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e13db55b5a0d447dea63cde772c1078405bbbf96 58c5ec23b1a238eb75cb0aba6f69d8f9e68ef0b2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e13db55b5a0d447dea63cde772c1078405bbbf96 fc16126cc11d9f507130bf84ab137ee0938c900e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.11","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.11 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.96 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.39 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.4 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64477","cve":"CVE-2026-64477","epss":"0.002090000","percentile":"0.111770000","score_date":"2026-07-25","updated_at":"2026-07-26 00:12:33"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["arch/x86/kernel/cpu/resctrl/monitor.c","fs/resctrl/monitor.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"ebc300b7ee0c669fa76a7a8858298ff32e296103","status":"affected","version":"e13db55b5a0d447dea63cde772c1078405bbbf96","versionType":"git"},{"lessThan":"be1567992417dc92133e74126de7a6066c825ac9","status":"affected","version":"e13db55b5a0d447dea63cde772c1078405bbbf96","versionType":"git"},{"lessThan":"58c5ec23b1a238eb75cb0aba6f69d8f9e68ef0b2","status":"affected","version":"e13db55b5a0d447dea63cde772c1078405bbbf96","versionType":"git"},{"lessThan":"fc16126cc11d9f507130bf84ab137ee0938c900e","status":"affected","version":"e13db55b5a0d447dea63cde772c1078405bbbf96","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/x86/kernel/cpu/resctrl/monitor.c","fs/resctrl/monitor.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.11"},{"lessThan":"6.11","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.96","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-rc2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.96","versionStartIncluding":"6.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.39","versionStartIncluding":"6.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.4","versionStartIncluding":"6.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc2","versionStartIncluding":"6.11","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86,fs/resctrl: Prevent out-of-bounds access while offlining CPU when SNC enabled\n\nThe architecture updates the cpu_mask in a domain's header to track which\nonline CPUs are associated with the domain. When this mask becomes empty\nthe architecture initiates offline of the domain that includes calling\non resctrl fs to offline the domain. If it is a monitoring domain in\nwhich LLC occupancy is tracked resctrl fs forces the limbo handler to\nclear all busy RMID state associated with the domain.\n\nThe limbo handler always reads the current event value associated with a\nbusy RMID irrespective of it being checked as part of regular \"is it still\nbusy\" check or whether it will be forced released anyway. When reading an\nRMID on a system with SNC enabled the \"logical RMID\" is converted to the\n\"physical RMID\" and this conversion requires the NUMA node ID of the\nresctrl monitoring domain that is in turn determined by querying the NUMA\nnode ID of any CPU belonging to the monitoring domain.\n\nWhen the monitoring domain is going offline its cpu_mask is empty causing\nthe NUMA node ID query via cpu_to_node() to be done with \"nr_cpu_ids\" as\nargument resulting in an out-of-bounds access.\n\nRefactor the limbo handler to skip reading the RMID when the RMID will\njust be forced to no longer be dirty in the domain anyway. Add a safety\ncheck to the architecture's RMID reader to protect against this scenario."}],"providerMetadata":{"dateUpdated":"2026-07-25T08:51:39.558Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/ebc300b7ee0c669fa76a7a8858298ff32e296103"},{"url":"https://git.kernel.org/stable/c/be1567992417dc92133e74126de7a6066c825ac9"},{"url":"https://git.kernel.org/stable/c/58c5ec23b1a238eb75cb0aba6f69d8f9e68ef0b2"},{"url":"https://git.kernel.org/stable/c/fc16126cc11d9f507130bf84ab137ee0938c900e"}],"title":"x86,fs/resctrl: Prevent out-of-bounds access while offlining CPU when SNC enabled","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64477","datePublished":"2026-07-25T08:51:39.558Z","dateReserved":"2026-07-19T15:36:31.791Z","dateUpdated":"2026-07-25T08:51:39.558Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-25 10:17:33","lastModifiedDate":"2026-07-25 10:17:33","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64477","Ordinal":"1","Title":"x86,fs/resctrl: Prevent out-of-bounds access while offlining CPU","CVE":"CVE-2026-64477","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64477","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86,fs/resctrl: Prevent out-of-bounds access while offlining CPU when SNC enabled\n\nThe architecture updates the cpu_mask in a domain's header to track which\nonline CPUs are associated with the domain. When this mask becomes empty\nthe architecture initiates offline of the domain that includes calling\non resctrl fs to offline the domain. If it is a monitoring domain in\nwhich LLC occupancy is tracked resctrl fs forces the limbo handler to\nclear all busy RMID state associated with the domain.\n\nThe limbo handler always reads the current event value associated with a\nbusy RMID irrespective of it being checked as part of regular \"is it still\nbusy\" check or whether it will be forced released anyway. When reading an\nRMID on a system with SNC enabled the \"logical RMID\" is converted to the\n\"physical RMID\" and this conversion requires the NUMA node ID of the\nresctrl monitoring domain that is in turn determined by querying the NUMA\nnode ID of any CPU belonging to the monitoring domain.\n\nWhen the monitoring domain is going offline its cpu_mask is empty causing\nthe NUMA node ID query via cpu_to_node() to be done with \"nr_cpu_ids\" as\nargument resulting in an out-of-bounds access.\n\nRefactor the limbo handler to skip reading the RMID when the RMID will\njust be forced to no longer be dirty in the domain anyway. Add a safety\ncheck to the architecture's RMID reader to protect against this scenario.","Type":"Description","Title":"x86,fs/resctrl: Prevent out-of-bounds access while offlining CPU"}]}}}