{"api_version":"1","generated_at":"2026-10-27T05:11:38+00:00","cve":"CVE-2026-93147","urls":{"html":"https://cve.report/CVE-2026-93147","api":"https://cve.report/api/cve/CVE-2026-93147.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-93147","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-93147"},"summary":{"title":"s390/bpf: Replace ly instruction with llgf","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/bpf: Replace ly instruction with llgf\n\ncpu_nr is a 32 bit value and BPF_REG_0 is a 64 bit register, when ly loads\nthe cpu_nr into BPF_REG_0 it does not zero the upper bits, but llgf does.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-17 17:18:09","updated_at":"2026-10-19 10:17:04"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/5f6cc299938b561cb01e343bab7042611fcee12a","name":"https://git.kernel.org/stable/c/5f6cc299938b561cb01e343bab7042611fcee12a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/88500a86ab79f01c568de6ed00f5b1c5c79f11d5","name":"https://git.kernel.org/stable/c/88500a86ab79f01c568de6ed00f5b1c5c79f11d5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-93147","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93147","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9012cf2491e3c5d28d098b0d6da804af82977032 88500a86ab79f01c568de6ed00f5b1c5c79f11d5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 9012cf2491e3c5d28d098b0d6da804af82977032 5f6cc299938b561cb01e343bab7042611fcee12a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.2","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.6 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"93147","cve":"CVE-2026-93147","epss":"0.001540000","percentile":"0.048950000","score_date":"2026-09-21","updated_at":"2026-09-22 00:03:18"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["arch/s390/net/bpf_jit_comp.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"88500a86ab79f01c568de6ed00f5b1c5c79f11d5","status":"affected","version":"9012cf2491e3c5d28d098b0d6da804af82977032","versionType":"git"},{"lessThan":"5f6cc299938b561cb01e343bab7042611fcee12a","status":"affected","version":"9012cf2491e3c5d28d098b0d6da804af82977032","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/s390/net/bpf_jit_comp.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.2"},{"lessThan":"7.2","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.6","versionStartIncluding":"7.2","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"7.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/bpf: Replace ly instruction with llgf\n\ncpu_nr is a 32 bit value and BPF_REG_0 is a 64 bit register, when ly loads\nthe cpu_nr into BPF_REG_0 it does not zero the upper bits, but llgf does."}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:L - The malformed input is eBPF bytecode containing BPF_JMP|BPF_CALL with imm=BPF_FUNC_get_smp_processor_id, loaded via bpf_prog_load() (bpf(2) BPF_PROG_LOAD). s390 bpf_jit_insn() then inlines that call as LY from get_lowcore()->cpu_nr; no remote protocol carries this bytecode.\nAC:L - The attacker sets BPF_REG_0 (s390 %r14) with BPF_LD_IMM64, then emits the helper call; bpf_jit_insn() always compiles it to LY (E358), which writes only bits 32-63 and leaves the attacker-chosen high half intact. bpf_opt_remove_dead_code() does not delete that store, and there is no race.\nPR:L - bpf_prog_load() allows BPF_PROG_TYPE_SOCKET_FILTER; sk_filter_func_proto() reaches bpf_base_func_proto(), which returns bpf_get_raw_smp_processor_id_proto for BPF_FUNC_get_smp_processor_id before its CAP_BPF gate, and BPF_MAP_TYPE_ARRAY is an unprivileged map. CAP_BPF is also granted by bpf_token_capable() in a delegated user namespace.\nUI:N - The attacker loads the crafted program with bpf(BPF_PROG_LOAD) and executes it themselves via BPF_PROG_TEST_RUN (sk_filter_prog_ops.test_run = bpf_prog_test_run_skb) or SO_ATTACH_BPF on their own socket; no other user must mount, open, or otherwise act.\nS:U - LY leaving stale high bits in BPF_REG_0 lets the JITed program read and write the host kernel through a verifier-approved PTR_TO_MAP_VALUE. That stays inside the same kernel authority; it is not a KVM guest-to-host or IOMMU bypass.\nC:H - do_refine_retval_range() sets R0’s 64-bit range to [0, nr_cpu_ids-1] after BPF_FUNC_get_smp_processor_id, so check_map_access() allows adding it to a map-value pointer. LY preserves attacker high bits, so the subsequent BPF_LDX reads kernel memory far outside the map.\nI:H - The same forged pointer is a BPF_STX destination: the store lands at map_value + ((old_r0 & 0xFFFFFFFF00000000) | cpu_nr). That is an attacker-controlled kernel write usable for corruption and control-flow hijack.\nA:H - Using that out-of-bounds map-value pointer (map_value plus the uncleared high 32 bits of %r14 after LY of cpu_nr) faults on unmapped addresses and oopses or panics the kernel."}]}],"providerMetadata":{"dateUpdated":"2026-10-19T09:06:19.689Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/88500a86ab79f01c568de6ed00f5b1c5c79f11d5"},{"url":"https://git.kernel.org/stable/c/5f6cc299938b561cb01e343bab7042611fcee12a"}],"title":"s390/bpf: Replace ly instruction with llgf","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-93147","datePublished":"2026-09-17T16:11:44.793Z","dateReserved":"2026-09-17T16:02:15.088Z","dateUpdated":"2026-10-19T09:06:19.689Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-17 17:18:09","lastModifiedDate":"2026-10-19 10:17:04","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"93147","Ordinal":"1","Title":"s390/bpf: Replace ly instruction with llgf","CVE":"CVE-2026-93147","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"93147","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ns390/bpf: Replace ly instruction with llgf\n\ncpu_nr is a 32 bit value and BPF_REG_0 is a 64 bit register, when ly loads\nthe cpu_nr into BPF_REG_0 it does not zero the upper bits, but llgf does.","Type":"Description","Title":"s390/bpf: Replace ly instruction with llgf"}]}}}