{"id":"CVE-2026-72066","state":"PUBLISHED","title":"cpu: hotplug: Bound hotplug states sysfs output","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncpu: hotplug: Bound hotplug states sysfs output\n\nstates_show() adds CPU hotplug state names into a single sysfs buffer\nusing sprintf(). With enough registered states, this can write past the\nend of the PAGE_SIZE buffer.\n\nUse sysfs_emit_at() so output is bounded.","publishedAt":"2026-08-15T05:52:19.527Z","updatedAt":"2026-10-19T21:19:26.150Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"27481cf4365a6ff5c9be3590143e7ed434000266","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"2408be459c70ef4250da1a9e50f5478e6b250d61","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"de4d3d8ae17dc8b4cf8c59436c4b7e2dc2491635","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"998f66e9ce320f3433f60b948e3698b744754a46","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"61a73a123ac7a7fbc57382531f8cb7092d569aba","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"6cb15b81ff545840048fb0e1a6e827d560dbf367","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"631d53102da9f469c96b882b770336bec095b833","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"86f436567f2516a0083b210bedc933544826a2c3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cpu.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.6","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.6","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cpu.c"]}],"references":["https://git.kernel.org/stable/c/27481cf4365a6ff5c9be3590143e7ed434000266","https://git.kernel.org/stable/c/2408be459c70ef4250da1a9e50f5478e6b250d61","https://git.kernel.org/stable/c/de4d3d8ae17dc8b4cf8c59436c4b7e2dc2491635","https://git.kernel.org/stable/c/998f66e9ce320f3433f60b948e3698b744754a46","https://git.kernel.org/stable/c/61a73a123ac7a7fbc57382531f8cb7092d569aba","https://git.kernel.org/stable/c/6cb15b81ff545840048fb0e1a6e827d560dbf367","https://git.kernel.org/stable/c/631d53102da9f469c96b882b770336bec095b833","https://git.kernel.org/stable/c/86f436567f2516a0083b210bedc933544826a2c3"],"weaknesses":["CWE-120"],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72066.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72066","state":"PUBLISHED","datePublished":"2026-08-15T05:52:19.527Z","dateUpdated":"2026-10-19T21:19:26.150Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-09T03:40:39.903Z"},"containers":{"cna":{"title":"cpu: hotplug: Bound hotplug states sysfs output","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncpu: hotplug: Bound hotplug states sysfs output\n\nstates_show() adds CPU hotplug state names into a single sysfs buffer\nusing sprintf(). With enough registered states, this can write past the\nend of the PAGE_SIZE buffer.\n\nUse sysfs_emit_at() so output is bounded."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"27481cf4365a6ff5c9be3590143e7ed434000266","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"2408be459c70ef4250da1a9e50f5478e6b250d61","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"de4d3d8ae17dc8b4cf8c59436c4b7e2dc2491635","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"998f66e9ce320f3433f60b948e3698b744754a46","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"61a73a123ac7a7fbc57382531f8cb7092d569aba","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"6cb15b81ff545840048fb0e1a6e827d560dbf367","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"631d53102da9f469c96b882b770336bec095b833","versionType":"git"},{"version":"98f8cdce1db580b99fce823a48eea2cb2bdb261e","status":"affected","lessThan":"86f436567f2516a0083b210bedc933544826a2c3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cpu.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.6","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.6","versionType":"semver"},{"version":"5.10.265","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/cpu.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/27481cf4365a6ff5c9be3590143e7ed434000266"},{"url":"https://git.kernel.org/stable/c/2408be459c70ef4250da1a9e50f5478e6b250d61"},{"url":"https://git.kernel.org/stable/c/de4d3d8ae17dc8b4cf8c59436c4b7e2dc2491635"},{"url":"https://git.kernel.org/stable/c/998f66e9ce320f3433f60b948e3698b744754a46"},{"url":"https://git.kernel.org/stable/c/61a73a123ac7a7fbc57382531f8cb7092d569aba"},{"url":"https://git.kernel.org/stable/c/6cb15b81ff545840048fb0e1a6e827d560dbf367"},{"url":"https://git.kernel.org/stable/c/631d53102da9f469c96b882b770336bec095b833"},{"url":"https://git.kernel.org/stable/c/86f436567f2516a0083b210bedc933544826a2c3"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The bug is in states_show() on the read path for /sys/devices/system/cpu/hotplug/states, reached only via a local sysfs/VFS read() syscall. No network packet handler, adjacent protocol, or physical attach path invokes this CPU hotplug sysfs callback.\nAC:L - Once enough CPU hotplug states are registered (plausible on cloud servers, KVM hosts, Android, and heavily configured distros with hundreds of cpuhp_setup_state() users), a single read deterministically executes unbounded sprintf() past the PAGE_SIZE buffer with no race or attacker-uncontrollable timing.\nPR:L - states is DEVICE_ATTR_RO (mode 0444), so any unprivileged local user can open and read /sys/devices/system/cpu/hotplug/states. states_show() performs no capability, namespace, or credential check before formatting output into the sysfs buffer.\nUI:N - Exploitation requires only the attacker reading the sysfs attribute; no victim mount, driver bind, module load, or other interactive action is needed beyond the attacker's own read once sufficient hotplug states exist at boot.\nS:U - The out-of-bounds write corrupts kernel heap memory within the same OS/kernel security authority. This is standard kernel memory corruption, not a KVM guest-to-host escape, IOMMU boundary bypass, or other cross-scope boundary violation.\nC:H - Unbounded sprintf() writes past the fixed PAGE_SIZE buffer allocated by sysfs_kf_seq_show(), corrupting adjacent kmalloc heap memory. Per kernel guidance, this class of memory-corruption OOB write can be leveraged for arbitrary kernel memory disclosure.\nI:H - The vulnerable loop advances buf and repeatedly sprintf()s without bounds, producing a kernel heap out-of-bounds write that can corrupt adjacent objects and enable control-flow hijacking or arbitrary kernel writes per OOB-write scoring guidance.\nA:H - Writing past the PAGE_SIZE sysfs show buffer corrupts adjacent kernel heap objects and can cause immediate kernel oops/panic during the read path or when corrupted adjacent allocations are later used, satisfying High availability impact."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-19T16:35:55.630Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"5.10.265"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"5.15.212"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-72066","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:51:15.720754Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-120","lang":"en","type":"CWE","description":"CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T21:19:26.150Z"}}]}}}