{"id":"CVE-2021-47368","state":"PUBLISHED","title":"enetc: Fix illegal access when reading affinity_hint","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nenetc: Fix illegal access when reading affinity_hint\n\nirq_set_affinity_hit() stores a reference to the cpumask_t\nparameter in the irq descriptor, and that reference can be\naccessed later from irq_affinity_hint_proc_show(). Since\nthe cpu_mask parameter passed to irq_set_affinity_hit() has\nonly temporary storage (it's on the stack memory), later\naccesses to it are illegal. Thus reads from the corresponding\nprocfs affinity_hint file can result in paging request oops.\n\nThe issue is fixed by the get_cpu_mask() helper, which provides\na permanent storage for the cpumask_t parameter.","publishedAt":"2024-05-21T15:03:34.494Z","updatedAt":"2026-08-05T08:47:29.151Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"4c4c3052911b577920353a7646e4883d5da40c28","versionType":"git"},{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"6c3f1b741c6c2914ea120e3a5790d3e900152f7b","versionType":"git"},{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"6f329d9da2a5ae032fcde800a99b118124ed5270","versionType":"git"},{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"7237a494decfa17d0b9d0076e6cee3235719de90","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/freescale/enetc/enetc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.1","versionType":"semver"},{"version":"5.4.150","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.70","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.14.9","status":"unaffected","lessThanOrEqual":"5.14.*","versionType":"semver"},{"version":"5.15","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/freescale/enetc/enetc.c"]}],"references":["https://git.kernel.org/stable/c/4c4c3052911b577920353a7646e4883d5da40c28","https://git.kernel.org/stable/c/6c3f1b741c6c2914ea120e3a5790d3e900152f7b","https://git.kernel.org/stable/c/6f329d9da2a5ae032fcde800a99b118124ed5270","https://git.kernel.org/stable/c/7237a494decfa17d0b9d0076e6cee3235719de90"],"weaknesses":["CWE-400"],"ingestedAt":"2026-10-29T19:49:19.404Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2021/47xxx/CVE-2021-47368.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2021-47368","state":"PUBLISHED","datePublished":"2024-05-21T15:03:34.494Z","dateUpdated":"2026-08-05T08:47:29.151Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-05-21T14:58:30.810Z"},"containers":{"cna":{"title":"enetc: Fix illegal access when reading affinity_hint","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nenetc: Fix illegal access when reading affinity_hint\n\nirq_set_affinity_hit() stores a reference to the cpumask_t\nparameter in the irq descriptor, and that reference can be\naccessed later from irq_affinity_hint_proc_show(). Since\nthe cpu_mask parameter passed to irq_set_affinity_hit() has\nonly temporary storage (it's on the stack memory), later\naccesses to it are illegal. Thus reads from the corresponding\nprocfs affinity_hint file can result in paging request oops.\n\nThe issue is fixed by the get_cpu_mask() helper, which provides\na permanent storage for the cpumask_t parameter."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"4c4c3052911b577920353a7646e4883d5da40c28","versionType":"git"},{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"6c3f1b741c6c2914ea120e3a5790d3e900152f7b","versionType":"git"},{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"6f329d9da2a5ae032fcde800a99b118124ed5270","versionType":"git"},{"version":"d4fd0404c1c95b17880f254ebfee3485693fa8ba","status":"affected","lessThan":"7237a494decfa17d0b9d0076e6cee3235719de90","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/freescale/enetc/enetc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.1","versionType":"semver"},{"version":"5.4.150","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.70","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.14.9","status":"unaffected","lessThanOrEqual":"5.14.*","versionType":"semver"},{"version":"5.15","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/freescale/enetc/enetc.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/4c4c3052911b577920353a7646e4883d5da40c28"},{"url":"https://git.kernel.org/stable/c/6c3f1b741c6c2914ea120e3a5790d3e900152f7b"},{"url":"https://git.kernel.org/stable/c/6f329d9da2a5ae032fcde800a99b118124ed5270"},{"url":"https://git.kernel.org/stable/c/7237a494decfa17d0b9d0076e6cee3235719de90"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires reading the local procfs file /proc/irq/<N>/affinity_hint; the dangling pointer is only dereferenced in irq_affinity_hint_proc_show() and is not reachable from network packet processing.\nAC:L - Once the ENETC interface is up (normal boot/ifup installs the stale hint in enetc_setup_irqs), a single cat of affinity_hint deterministically dereferences the dangling stack pointer with no race or attacker-uncontrolled memory layout to guess.\nPR:L - affinity_hint is created with mode 0444 (S_IRUGO), so any unprivileged local user can read it; the dangling pointer is installed by privileged ifup as part of normal operation, not by the attacker.\nUI:N - The attacker directly reads the procfs entry; no victim action is required because the ENETC interface is already brought up during normal system operation.\nS:U - The stale pointer dereference and resulting leak/oops remain entirely within the kernel's security authority, with no VM escape, IOMMU bypass, or sandbox boundary crossing.\nC:H - This is a use-after-free read of freed/reused kernel stack memory that cpumask_copy() copies out to unprivileged userspace via seq_printf, enabling repeatable disclosure of kernel stack contents including pointers that can defeat KASLR.\nI:N - The affinity_hint pointer is only stored, read, and cleared; nothing writes through the stale pointer and it is never used as a function pointer, so the attacker gains no kernel-state modification capability.\nA:H - As stated in the fix, reading affinity_hint can cause a paging-request oops when the referenced stack memory has been unmapped (e.g. under VMAP_STACK), and the fault occurs while holding desc->lock with IRQs disabled, which can panic or hang the system."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T08:47:29.151Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"5.4.150"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"5.10.70"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"5.14.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.1","versionEndExcluding":"5.15"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","affected":[{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"d4fd0404c1c9","status":"affected","lessThan":"4c4c3052911b","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"d4fd0404c1c9","status":"affected","lessThan":"6c3f1b741c6c","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"d4fd0404c1c9","status":"affected","lessThan":"6f329d9da2a5","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"d4fd0404c1c9","status":"affected","lessThan":"7237a494decf","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"5.1","status":"affected"}],"cpes":["cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"0","status":"unaffected","lessThan":"5.1","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"5.4.150","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"5.10.70","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"5.14.9","status":"unaffected","lessThanOrEqual":"5.14.*","versionType":"custom"}],"cpes":["cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*"]},{"vendor":"linux","product":"linux_kernel","defaultStatus":"unknown","versions":[{"version":"5.15","status":"unaffected"}],"cpes":["cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*"]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":8.1,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2024-06-05T20:50:21.709936Z","id":"CVE-2021-47368","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","type":"CWE","lang":"en","description":"CWE-400 Uncontrolled Resource Consumption"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-06-05T20:50:27.716Z"}},{"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/4c4c3052911b577920353a7646e4883d5da40c28","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/6c3f1b741c6c2914ea120e3a5790d3e900152f7b","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/6f329d9da2a5ae032fcde800a99b118124ed5270","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/7237a494decfa17d0b9d0076e6cee3235719de90","tags":["x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-04T05:32:08.655Z"}}]}}}