{ "cveId": "CVE-2026-64036", "url": "https://patchblox.com/security/cve/CVE-2026-64036", "summary": "CVE-2026-64036 is fixed in 20 products on 1 platform, first by ALAS2023-2026-1881, released June 22, 2026. It is not reported as exploited. Patch Radar priority: High.", "title": "cgroup/rstat: validate cpu before css_rstat_cpu() access", "description": "In the Linux kernel, the following vulnerability has been resolved: cgroup/rstat: validate cpu before css_rstat_cpu() access css_rstat_updated() is exposed as a BPF kfunc and accepts a caller-provided cpu argument. The function uses cpu for per-cpu rstat lookups without checking whether it refers to a valid possible CPU. A BPF iter/cgroup program with CAP_BPF and CAP_PERFMON can pass an invalid cpu value. On an unfixed UBSCAN_BOUNDS test kernel, cpu == 0x7fffffff triggers: UBSAN: array-index-out-of-bounds in kernel/cgroup/rstat.c:31:9 index 2147483647 is out of range for type \u0027long unsigned int [64]\u0027 Call Trace: css_rstat_updated bpf_iter_run_prog cgroup_iter_seq_show bpf_seq_read Add cpu validation to the BPF-facing css_rstat_updated() kfunc and move the common implementation to __css_rstat_updated() for in-kernel callers.", "published": "2026-06-22T09:00:00Z", "severity": "Moderate", "cvss": 7.8, "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "epss": 0.0013, "epssPercentile": 0.02623, "priority": "High", "priorityTier": 3, "exploited": false, "vendorExploited": false, "disclosed": false, "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-64036", "fixes": [ { "platform": "linux", "product": "bpftool6.18", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "bpftool6.18-debuginfo", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel-livepatch-6.18.35-68.127", "release": "amzn 2023", "fixedVersion": "1:1.0-0.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-debuginfo", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-debuginfo-common-aarch64", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-debuginfo-common-x86_64", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-devel", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-headers", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-modules-extra", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-modules-extra-common", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-tools", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-tools-debuginfo", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "kernel6.18-tools-devel", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "linux", "release": "Debian 13.5 (trixie)", "fixedVersion": "6.12.115-2", "fix": "DEBIAN-CVE-2026-64036", "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-64036", "released": "2026-07-20T12:58:36Z" }, { "platform": "linux", "product": "linux", "release": "Debian 14", "fixedVersion": "7.0.12-1", "fix": "DEBIAN-CVE-2026-64036", "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-64036", "released": "2026-07-20T12:58:36Z" }, { "platform": "linux", "product": "microvm-kernel6.18", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "perf6.18", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "perf6.18-debuginfo", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "python3-perf6.18", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" }, { "platform": "linux", "product": "python3-perf6.18-debuginfo", "release": "amzn 2023", "fixedVersion": "1:6.18.35-68.127.amzn2023", "fix": "ALAS2023-2026-1881", "url": "https://patchblox.com/security/fix/linux/alas2023-2026-1881", "released": "2026-06-22T09:00:00Z" } ], "noFixYet": [], "dataAsOf": "2026-11-08T13:06:02Z", "attribution": { "text": "Data: Patchblox Patch Radar", "url": "https://patchblox.com/security/patch-radar", "terms": "https://patchblox.com/security/patch-radar/use-the-data" } }