CVE-2026-98376

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98376", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.345Z", "datePublished": "2026-10-09T07:34:17.043Z", "dateUpdated": "2026-10-24T14:08:36.004Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:08:36.004Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Use array_map_meta_equal for percpu array inner map replacement\n\npercpu_array_map_ops.map_meta_equal points to the generic\nbpf_map_meta_equal(), which does not compare max_entries. When a\npercpu array serves as an inner map, replacing it with one that has\nfewer max_entries bypasses the check. Since percpu_array_map_gen_lookup()\ninlines the original template's index_mask as a JIT immediate, a lookup\non the replacement map can access pptrs[] out of bounds.\n\nPoint percpu_array_map_ops.map_meta_equal to array_map_meta_equal(),\nwhich already enforces the max_entries equality check.\n\nAdd a selftest to verify that replacing a percpu array inner map with\na differently-sized one is rejected."}], "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 local bpf(BPF_MAP_UPDATE_ELEM) path reaches map_update_elem()->bpf_map_update_value()->bpf_fd_array_map_update_elem()->bpf_map_fd_get_ptr(), where the patched percpu_array_map_ops.map_meta_equal validates the replacement map; no network handler supplies its FD or dimensions.\nAC:L - The attacker chooses the template and replacement max_entries, lookup key, program, and trigger; an index below the template limit but beyond the replacement deterministically reads pptrs[] out of bounds. No race or other actor is required on a JIT-enabled x86-64 or arm64 target.\nPR:L - map_create() places PERCPU_ARRAY and ARRAY_OF_MAPS in its unprivileged branch, and bpf_prog_load() permits SOCKET_FILTER without CAP_BPF when unprivileged BPF is enabled; alternatively, a user-namespace BPF token satisfies the gates without init-namespace root.\nUI:N - The attacker creates and replaces the maps, loads the lookup program, attaches it through SO_ATTACH_BPF to their own socket, and sends the triggering data themselves; no victim action is needed.\nS:U - percpu_array_map_gen_lookup() converts the out-of-bounds pptrs[] slot into a pointer used against the same host kernel's memory; this is ordinary kernel privilege escalation, not a guest-to-host, IOMMU, or other security-authority crossing.\nC:H - percpu_array_map_gen_lookup() loads a 64-bit pptrs[index] out of bounds and returns its adjusted value as a verifier-trusted map-value pointer. Because bpf_map_area_alloc() kmallocs the flexible object, map spraying can place chosen bytes at that slot, enabling kernel reads copied into another map.\nI:H - The forged PTR_TO_MAP_VALUE is writable because default map flags grant BPF_MAP_CAN_WRITE; direct BPF stores through an attacker-groomed out-of-bounds pptrs[] value therefore provide an arbitrary kernel-write primitive suitable for control-flow hijacking.\nA:H - Without successful grooming, BPF_MOV64_PERCPU_REG adjusts the garbage pointer loaded beyond pptrs[] and the attacker's next value access dereferences it, causing a kernel oops or panic; the attacker can repeatedly run the same socket-filter program."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/bpf/arraymap.c", "tools/testing/selftests/bpf/prog_tests/percpu_array_inner_map.c"], "versions": [{"version": "db69718b8efac802c7cc20d5a6c7dfc913f99c43", "lessThan": "593980175389a05793f6060aa20e626330960395", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/bpf/arraymap.c", "tools/testing/selftests/bpf/prog_tests/percpu_array_inner_map.c"], "versions": [{"version": "6.10", "status": "affected"}, {"version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver"}, {"version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "7.1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/593980175389a05793f6060aa20e626330960395"}], "title": "bpf: Use array_map_meta_equal for percpu array inner map replacement", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/bpf/arraymap.c", "tools/testing/selftests/bpf/prog_tests/percpu_array_inner_map.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "593980175389a05793f6060aa20e626330960395", "status": "affected", "version": "db69718b8efac802c7cc20d5a6c7dfc913f99c43", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/bpf/arraymap.c", "tools/testing/selftests/bpf/prog_tests/percpu_array_inner_map.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.10"}, {"lessThan": "6.10", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Use array_map_meta_equal for percpu array inner map replacement\n\npercpu_array_map_ops.map_meta_equal points to the generic\nbpf_map_meta_equal(), which does not compare max_entries. When a\npercpu array serves as an inner map, replacing it with one that has\nfewer max_entries bypasses the check. Since percpu_array_map_gen_lookup()\ninlines the original template's index_mask as a JIT immediate, a lookup\non the replacement map can access pptrs[] out of bounds.\n\nPoint percpu_array_map_ops.map_meta_equal to array_map_meta_equal(),\nwhich already enforces the max_entries equality check.\n\nAdd a selftest to verify that replacing a percpu array inner map with\na differently-sized one is rejected."}], "id": "CVE-2026-98376", "lastModified": "2026-10-24T14:16:39.733", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-10-09T08:16:55.910", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/593980175389a05793f6060aa20e626330960395"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: bpf: Use array_map_meta_equal for percpu array inner map replacement", "id": "2548397", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2548397"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-125", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbpf: Use array_map_meta_equal for percpu array inner map replacement\npercpu_array_map_ops.map_meta_equal points to the generic\nbpf_map_meta_equal(), which does not compare max_entries. When a\npercpu array serves as an inner map, replacing it with one that has\nfewer max_entries bypasses the check. Since percpu_array_map_gen_lookup()\ninlines the original template's index_mask as a JIT immediate, a lookup\non the replacement map can access pptrs[] out of bounds.\nPoint percpu_array_map_ops.map_meta_equal to array_map_meta_equal(),\nwhich already enforces the max_entries equality check.\nAdd a selftest to verify that replacing a percpu array inner map with\na differently-sized one is rejected.", "A flaw was found in the Linux kernel's BPF (Berkeley Packet Filter) subsystem. When replacing an inner per-CPU array map within a map-in-map structure, the kernel fails to verify that the replacement map matches the size of the original template map. A local attacker can exploit this flaw by substituting an inner map with one that has fewer entries, causing subsequent lookups to perform out-of-bounds memory access. This issue can lead to kernel memory corruption, resulting in a system crash (Denial of Service) or potential privilege escalation."], "name": "CVE-2026-98376", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "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": "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"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-09T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98376\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98376\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98376.mbox"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[db69718b8efac802c7cc20d5a6c7dfc913f99c43,593980175389a05793f6060aa20e626330960395)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.10"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.10)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-10-09T09:45:04.784305+00:00", "updated": "2026-10-24T15:45:07.134925+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}