CVE-2026-92518

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-92518", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-16T12:21:13.873Z", "datePublished": "2026-09-17T16:10:26.136Z", "dateUpdated": "2026-10-19T09:04:24.705Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:04:24.705Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nriscv, bpf: Fix kernel stack corruption in tailcall with CFI\n\nWhen CONFIG_CFI_CLANG is enabled, prog->bpf_func already skips the kcfi\ninstruction during setup. Including it again in the tailcall jump offset\ncauses it to jump over an extra 4 bytes, skipping the stack pointer\nadjustment, which will result in kernel stack corruption."}], "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 attacker-controlled input is a BPF program that uses bpf_tail_call, loaded via bpf(BPF_PROG_LOAD) in __sys_bpf(). emit_bpf_tail_call() then calls __build_epilogue(true), which emits the miscomputed jalr; no remote protocol carries that bytecode.\nAC:L - On CONFIG_CFI, bpf_int_jit_compile() sets prog->bpf_func to ro_insns+cfi_get_offset() (skipping the kcfi word), while __build_epilogue() still adds RV_KCFI_NINSNS to the jalr immediate, so every tail call lands past the prologue addi-to-SP. The attacker loads the caller/callee and runs them; no race or uninfluenced layout is required.\nPR:L - bpf_prog_load() allows BPF_PROG_TYPE_SOCKET_FILTER without CAP_BPF when unprivileged BPF is enabled, BPF_MAP_TYPE_PROG_ARRAY is created without CAP_BPF, and bpf_base_func_proto() returns bpf_tail_call_proto before the CAP_PERFMON gate. Otherwise only CAP_BPF or a delegated BPF token is required, not init-namespace root.\nUI:N - The attacker loads both programs, updates the PROG_ARRAY, and runs the caller with bpf(BPF_PROG_TEST_RUN) (sk_filter_prog_ops.test_run = bpf_prog_test_run_skb) or setsockopt(SO_ATTACH_BPF) on a socket they own. No other user must mount, open, or click.\nS:U - The skipped stack allocation corrupts the host kernel stack of the thread running the JITed image (bpf_prog_test_run_skb or sk_filter_trim_cap). That is in-kernel memory corruption on the same authority, not a KVM/Xen guest-to-host or IOMMU boundary crossing.\nC:H - After the tailcall jalr skips emit_addi(SP, SP, -stack_adjust), bpf_jit_build_prologue() still does emit_addi(S5, SP, bpf_stack_adjust), so BPF_REG_FP addresses the kernel caller's frame. FP-relative LDX then reads saved return addresses and locals from that frame.\nI:H - The same missed SP subtract means prologue sd of RA/FP/S1\u2013S6 and BPF STX through S5 write into the kernel frame above SP. The callee epilogue then addi SP, SP, stack_adjust and jalr RA on that smashed frame, enabling a stack pivot and control-flow hijack.\nA:H - Returning from the tail-call target with SP still at the pre-BPF kernel SP, then adding stack_adjust in __build_epilogue(), misaligns the caller of bpf_prog_run so the kernel oopses or panics; any such crash is Availability High."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/riscv/net/bpf_jit_comp64.c"], "versions": [{"version": "30a59cc79754fd9ff3f41b7ee2eb21da85988548", "lessThan": "34b1bb33a025787e05f966e74de18cd36276f801", "status": "affected", "versionType": "git"}, {"version": "30a59cc79754fd9ff3f41b7ee2eb21da85988548", "lessThan": "a6e11a81da3420fd37f1518d4f238c4d5784086e", "status": "affected", "versionType": "git"}, {"version": "30a59cc79754fd9ff3f41b7ee2eb21da85988548", "lessThan": "52fb1756ea1d2759dfef2d86245be00b05dac3a2", "status": "affected", "versionType": "git"}, {"version": "fe5b68fdcec0f3d97a32f4c4acfef59cf90718f7", "status": "affected", "versionType": "git"}, {"version": "6.11.6", "lessThan": "6.12", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/riscv/net/bpf_jit_comp64.c"], "versions": [{"version": "6.12", "status": "affected"}, {"version": "0", "lessThan": "6.12", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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": "6.12", "versionEndExcluding": "6.18.52"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "7.2.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "7.3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.11.6"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/34b1bb33a025787e05f966e74de18cd36276f801"}, {"url": "https://git.kernel.org/stable/c/a6e11a81da3420fd37f1518d4f238c4d5784086e"}, {"url": "https://git.kernel.org/stable/c/52fb1756ea1d2759dfef2d86245be00b05dac3a2"}], "title": "riscv, bpf: Fix kernel stack corruption in tailcall with CFI", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["arch/riscv/net/bpf_jit_comp64.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "34b1bb33a025787e05f966e74de18cd36276f801", "status": "affected", "version": "30a59cc79754fd9ff3f41b7ee2eb21da85988548", "versionType": "git"}, {"lessThan": "a6e11a81da3420fd37f1518d4f238c4d5784086e", "status": "affected", "version": "30a59cc79754fd9ff3f41b7ee2eb21da85988548", "versionType": "git"}, {"lessThan": "52fb1756ea1d2759dfef2d86245be00b05dac3a2", "status": "affected", "version": "30a59cc79754fd9ff3f41b7ee2eb21da85988548", "versionType": "git"}, {"status": "affected", "version": "fe5b68fdcec0f3d97a32f4c4acfef59cf90718f7", "versionType": "git"}, {"lessThan": "6.12", "status": "affected", "version": "6.11.6", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["arch/riscv/net/bpf_jit_comp64.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": "6.18.*", "status": "unaffected", "version": "6.18.52", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "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\nriscv, bpf: Fix kernel stack corruption in tailcall with CFI\n\nWhen CONFIG_CFI_CLANG is enabled, prog->bpf_func already skips the kcfi\ninstruction during setup. Including it again in the tailcall jump offset\ncauses it to jump over an extra 4 bytes, skipping the stack pointer\nadjustment, which will result in kernel stack corruption."}], "id": "CVE-2026-92518", "lastModified": "2026-10-19T10:16:52.303", "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": "2026-09-17T17:17:54.687", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/34b1bb33a025787e05f966e74de18cd36276f801"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/52fb1756ea1d2759dfef2d86245be00b05dac3a2"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a6e11a81da3420fd37f1518d4f238c4d5784086e"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[30a59cc79754fd9ff3f41b7ee2eb21da85988548,34b1bb33a025787e05f966e74de18cd36276f801)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[30a59cc79754fd9ff3f41b7ee2eb21da85988548,a6e11a81da3420fd37f1518d4f238c4d5784086e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[30a59cc79754fd9ff3f41b7ee2eb21da85988548,52fb1756ea1d2759dfef2d86245be00b05dac3a2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "fe5b68fdcec0f3d97a32f4c4acfef59cf90718f7"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.11.6,6.12)"}}], "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": "6.12"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.12)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.52,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2.6,7.2.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc1,*]"}}], "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": "2026-09-19T09:45:03.926422+00:00", "updated": "2026-09-19T22:45:06.158809+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-787"]}