{"api_version":"1","generated_at":"2026-08-25T08:07:20+00:00","cve":"CVE-2026-72111","urls":{"html":"https://cve.report/CVE-2026-72111","api":"https://cve.report/api/cve/CVE-2026-72111.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-72111","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-72111"},"summary":{"title":"bpf: Reset register bounds before narrowing retval range in check_mem_access()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reset register bounds before narrowing retval range in check_mem_access()\n\nWhen the BPF verifier processes a context load of an LSM hook return\nvalue, it calls __mark_reg_s32_range() to narrow the register to the\nhook's valid range. However, __mark_reg_s32_range() intersects the new\nrange with the register's existing bounds using max_t()/min_t() rather\nthan replacing them.\n\nIf the destination register carries stale bounds from a prior instruction\n(e.g. BPF_MOV64_IMM), the intersection can produce a range narrower than\nreality. The verifier then believes it knows the register's exact value,\nwhile at runtime the actual hook return value is loaded, creating a\nverifier/runtime mismatch that can be used to bypass BPF memory safety\nchecks.\n\nThe else branch already calls mark_reg_unknown() to reset register state\nbefore any narrowing. Apply the same reset in the is_retval path so\nstale bounds are cleared before __mark_reg_s32_range() intersects.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-15 06:21:25","updated_at":"2026-08-17 06:18:10"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"8.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"8.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","data":{"baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/0993dc5fc619c0b25ab1310cb11d65e78351c0fe","name":"https://git.kernel.org/stable/c/0993dc5fc619c0b25ab1310cb11d65e78351c0fe","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5a55f9aecc08990940e70f0c7048a80850c5a16a","name":"https://git.kernel.org/stable/c/5a55f9aecc08990940e70f0c7048a80850c5a16a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bde92f65042ec14389782dd223f706bf6b59ce5d","name":"https://git.kernel.org/stable/c/bde92f65042ec14389782dd223f706bf6b59ce5d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5e0b273e0a62cc04ec338c7b502797c66c2ed42a","name":"https://git.kernel.org/stable/c/5e0b273e0a62cc04ec338c7b502797c66c2ed42a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-72111","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72111","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5d99e198be279045e6ecefe220f5c52f8ce9bfd5 bde92f65042ec14389782dd223f706bf6b59ce5d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5d99e198be279045e6ecefe220f5c52f8ce9bfd5 0993dc5fc619c0b25ab1310cb11d65e78351c0fe git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5d99e198be279045e6ecefe220f5c52f8ce9bfd5 5a55f9aecc08990940e70f0c7048a80850c5a16a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5d99e198be279045e6ecefe220f5c52f8ce9bfd5 5e0b273e0a62cc04ec338c7b502797c66c2ed42a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1050727d83e70449991c29dd1cf29fe936a63da3 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 27ca3e20fe80be85a92b10064dfeb56cb2564b1c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.10.13 6.11 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.11.2 6.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.103 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.40 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.5 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"72111","cve":"CVE-2026-72111","epss":"0.001720000","percentile":"0.068830000","score_date":"2026-08-17","updated_at":"2026-08-18 00:11:47"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["kernel/bpf/verifier.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"bde92f65042ec14389782dd223f706bf6b59ce5d","status":"affected","version":"5d99e198be279045e6ecefe220f5c52f8ce9bfd5","versionType":"git"},{"lessThan":"0993dc5fc619c0b25ab1310cb11d65e78351c0fe","status":"affected","version":"5d99e198be279045e6ecefe220f5c52f8ce9bfd5","versionType":"git"},{"lessThan":"5a55f9aecc08990940e70f0c7048a80850c5a16a","status":"affected","version":"5d99e198be279045e6ecefe220f5c52f8ce9bfd5","versionType":"git"},{"lessThan":"5e0b273e0a62cc04ec338c7b502797c66c2ed42a","status":"affected","version":"5d99e198be279045e6ecefe220f5c52f8ce9bfd5","versionType":"git"},{"status":"affected","version":"1050727d83e70449991c29dd1cf29fe936a63da3","versionType":"git"},{"status":"affected","version":"27ca3e20fe80be85a92b10064dfeb56cb2564b1c","versionType":"git"},{"lessThan":"6.11","status":"affected","version":"6.10.13","versionType":"semver"},{"lessThan":"6.12","status":"affected","version":"6.11.2","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/bpf/verifier.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.12"},{"lessThan":"6.12","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.103","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.40","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.5","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.103","versionStartIncluding":"6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.40","versionStartIncluding":"6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.5","versionStartIncluding":"6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reset register bounds before narrowing retval range in check_mem_access()\n\nWhen the BPF verifier processes a context load of an LSM hook return\nvalue, it calls __mark_reg_s32_range() to narrow the register to the\nhook's valid range. However, __mark_reg_s32_range() intersects the new\nrange with the register's existing bounds using max_t()/min_t() rather\nthan replacing them.\n\nIf the destination register carries stale bounds from a prior instruction\n(e.g. BPF_MOV64_IMM), the intersection can produce a range narrower than\nreality. The verifier then believes it knows the register's exact value,\nwhile at runtime the actual hook return value is loaded, creating a\nverifier/runtime mismatch that can be used to bypass BPF memory safety\nchecks.\n\nThe else branch already calls mark_reg_unknown() to reset register state\nbefore any narrowing. Apply the same reset in the is_retval path so\nstale bounds are cleared before __mark_reg_s32_range() intersects."}],"metrics":[{"cvssV3_1":{"baseScore":8.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:L - The flaw is reached only through bpf(BPF_PROG_LOAD) during bpf_check()->check_mem_access() when a BPF_LSM_MAC program loads the LSM hook return value from PTR_TO_CTX; per kernel CNA guidance BPF verifier issues are Local even if attached programs later run on file, socket, or network LSM hooks.\nAC:L - An attacker fully controls the BPF instruction sequence (e.g., BPF_MOV64_IMM to leave stale bounds, then a ctx retval load) and can deterministically force __mark_reg_s32_range() to intersect into an overly narrow range without races, special memory layout, or other uncontrollable conditions.\nPR:L - Loading BPF_PROG_TYPE_LSM programs requires CAP_BPF and CAP_PERFMON (is_perfmon_prog_type), both blocked for unprivileged users when kernel.unprivileged_bpf_disabled is set but obtainable inside user namespaces on typical CONFIG_BPF_LSM systems per kernel CNA BPF guidance.\nUI:N - No victim interaction is required; the attacker loads, verifies, and attaches their own malicious BPF LSM program and triggers the attached LSM hook with their own local syscalls or network operations.\nS:C - A container or user-namespace tenant with namespace-granted CAP_BPF can load a verifier-bypassing BPF LSM program whose runtime memory corruption executes in host kernel context on LSM hook firing, crossing the container-to-host security boundary on multi-tenant cloud and Android-style deployments.\nC:H - The verifier/runtime register-bounds mismatch lets unsafe BPF programs pass verification and perform out-of-bounds reads on ctx, stack, or map memory at runtime, a memory-corruption primitive that can be developed into arbitrary kernel memory disclosure.\nI:H - False exact-knowledge of the LSM return-value register enables verifier-approved pointer arithmetic and memory writes that are invalid at runtime, enabling out-of-bounds writes and control-flow hijacking toward arbitrary kernel code execution from BPF context.\nA:H - Running verifier-incorrect BPF LSM programs can trigger kernel oops or panic from corrupted memory accesses, and once attached the attacker can repeatedly invoke the hook to cause repeatable host-wide denial of service."}]}],"providerMetadata":{"dateUpdated":"2026-08-17T05:40:25.647Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/bde92f65042ec14389782dd223f706bf6b59ce5d"},{"url":"https://git.kernel.org/stable/c/0993dc5fc619c0b25ab1310cb11d65e78351c0fe"},{"url":"https://git.kernel.org/stable/c/5a55f9aecc08990940e70f0c7048a80850c5a16a"},{"url":"https://git.kernel.org/stable/c/5e0b273e0a62cc04ec338c7b502797c66c2ed42a"}],"title":"bpf: Reset register bounds before narrowing retval range in check_mem_access()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-72111","datePublished":"2026-08-15T05:52:52.538Z","dateReserved":"2026-08-09T03:40:39.906Z","dateUpdated":"2026-08-17T05:40:25.647Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-15 06:21:25","lastModifiedDate":"2026-08-17 06:18:10","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:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":2,"impactScore":6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"72111","Ordinal":"1","Title":"bpf: Reset register bounds before narrowing retval range in chec","CVE":"CVE-2026-72111","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"72111","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reset register bounds before narrowing retval range in check_mem_access()\n\nWhen the BPF verifier processes a context load of an LSM hook return\nvalue, it calls __mark_reg_s32_range() to narrow the register to the\nhook's valid range. However, __mark_reg_s32_range() intersects the new\nrange with the register's existing bounds using max_t()/min_t() rather\nthan replacing them.\n\nIf the destination register carries stale bounds from a prior instruction\n(e.g. BPF_MOV64_IMM), the intersection can produce a range narrower than\nreality. The verifier then believes it knows the register's exact value,\nwhile at runtime the actual hook return value is loaded, creating a\nverifier/runtime mismatch that can be used to bypass BPF memory safety\nchecks.\n\nThe else branch already calls mark_reg_unknown() to reset register state\nbefore any narrowing. Apply the same reset in the is_retval path so\nstale bounds are cleared before __mark_reg_s32_range() intersects.","Type":"Description","Title":"bpf: Reset register bounds before narrowing retval range in chec"}]}}}