CVE-2024-47702

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2024-47702", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-09-30T16:00:12.945Z", "datePublished": "2024-10-21T11:53:37.958Z", "dateUpdated": "2026-10-03T10:55:18.539Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-03T10:55:18.539Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fail verification for sign-extension of packet data/data_end/data_meta\n\nsyzbot reported a kernel crash due to\n commit 1f1e864b6555 (\"bpf: Handle sign-extenstin ctx member accesses\").\nThe reason is due to sign-extension of 32-bit load for\npacket data/data_end/data_meta uapi field.\n\nThe original code looks like:\n r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\n r3 = *(u32 *)(r1 + 80) /* load __sk_buff->data_end */\n r0 = r2\n r0 += 8\n if r3 > r0 goto +1\n ...\nNote that __sk_buff->data load has 32-bit sign extension.\n\nAfter verification and convert_ctx_accesses(), the final asm code looks like:\n r2 = *(u64 *)(r1 +208)\n r2 = (s32)r2\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\n ...\nNote that 'r2 = (s32)r2' may make the kernel __sk_buff->data address invalid\nwhich may cause runtime failure.\n\nCurrently, in C code, typically we have\n void *data = (void *)(long)skb->data;\n void *data_end = (void *)(long)skb->data_end;\n ...\nand it will generate\n r2 = *(u64 *)(r1 +208)\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\n\nIf we allow sign-extension,\n void *data = (void *)(long)(int)skb->data;\n void *data_end = (void *)(long)skb->data_end;\n ...\nthe generated code looks like\n r2 = *(u64 *)(r1 +208)\n r2 <<= 32\n r2 s>>= 32\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\nand this will cause verification failure since \"r2 <<= 32\" is not allowed\nas \"r2\" is a packet pointer.\n\nTo fix this issue for case\n r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\nthis patch added additional checking in is_valid_access() callback\nfunction for packet data/data_end/data_meta access. If those accesses\nare with sign-extenstion, the verification will fail.\n\n [1] https://lore.kernel.org/bpf/000000000000c90eee061d236d37@google.com/"}], "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 vulnerability is reached by loading a crafted eBPF program through the bpf(BPF_PROG_LOAD) syscall, which requires local access to the system; the attacker supplies the malicious LDSX instruction, not a remote peer.\nAC:L - The attacker authors the BPF bytecode directly, so the verifier bypass is accepted deterministically on every load, and the corrupted `(s32)skb->data` pointer is produced on every execution of the program with no race or unpredictable precondition; running the hook repeatedly over many skbs makes the out-of-bounds dereference a certainty.\nPR:L - Loading the affected program types requires CAP_BPF/CAP_NET_ADMIN, which BPF token delegation (`bpf_token_capable()` \u2192 `bpf_ns_capable(token->userns, cap)`, present in the affected 6.9\u20136.11 range) makes available to a host-unprivileged user inside a user namespace, and CAP_BPF is by design a reduced privilege whose security boundary is the verifier itself.\nUI:N - The attacker loads and attaches the program and then generates the traffic (or uses BPF_PROG_TEST_RUN) that executes it; no action from any other user is needed.\nS:U - The out-of-bounds access and resulting corruption occur within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The verifier still tracks the truncated value as a valid PTR_TO_PACKET, so the program performs kernel-mode reads at `(s32)skb->data + K` far outside any packet buffer and can copy the results into a BPF map or the packet, giving an out-of-bounds kernel memory read primitive.\nI:H - `may_access_direct_pkt_data()` grants direct packet writes to SCHED_CLS, SCHED_ACT, XDP, LWT_XMIT and SK_SKB, so the same corrupted pointer yields kernel-mode stores at an attacker-influenced address \u2014 memory corruption exploitable for further escalation.\nA:H - syzbot reported this as a kernel crash; dereferencing the mangled address from softirq/NAPI context produces a page fault or general protection fault in kernel mode, oopsing or panicking the machine."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/bpf.h", "kernel/bpf/verifier.c", "net/core/filter.c"], "versions": [{"version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "4b48228eebce2ab1b01e3133da822164472b7e46", "status": "affected", "versionType": "git"}, {"version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "f1620c93a1ec950d87ef327a565d3907736d3340", "status": "affected", "versionType": "git"}, {"version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "f09757fe97a225ae505886eac572e4cbfba96537", "status": "affected", "versionType": "git"}, {"version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "92de36080c93296ef9005690705cba260b9bd68a", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/linux/bpf.h", "kernel/bpf/verifier.c", "net/core/filter.c"], "versions": [{"version": "6.6", "status": "affected"}, {"version": "0", "lessThan": "6.6", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.10.13", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.11.2", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12", "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": "6.6", "versionEndExcluding": "6.6.158"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.10.13"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.11.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.12"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/4b48228eebce2ab1b01e3133da822164472b7e46"}, {"url": "https://git.kernel.org/stable/c/f1620c93a1ec950d87ef327a565d3907736d3340"}, {"url": "https://git.kernel.org/stable/c/f09757fe97a225ae505886eac572e4cbfba96537"}, {"url": "https://git.kernel.org/stable/c/92de36080c93296ef9005690705cba260b9bd68a"}], "title": "bpf: Fail verification for sign-extension of packet data/data_end/data_meta", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2024-47702", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2024-10-21T13:04:24.861686Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-21T13:14:13.443Z"}}]}}

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running the hook repeatedly over many skbs makes the out-of-bounds dereference a certainty.\nPR:L - Loading the affected program types requires CAP_BPF/CAP_NET_ADMIN, which BPF token delegation (`bpf_token_capable()` \u2192 `bpf_ns_capable(token->userns, cap)`, present in the affected 6.9\u20136.11 range) makes available to a host-unprivileged user inside a user namespace, and CAP_BPF is by design a reduced privilege whose security boundary is the verifier itself.\nUI:N - The attacker loads and attaches the program and then generates the traffic (or uses BPF_PROG_TEST_RUN) that executes it; no action from any other user is needed.\nS:U - The out-of-bounds access and resulting corruption occur within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The verifier still tracks the truncated value as a valid PTR_TO_PACKET, so the program performs kernel-mode reads at `(s32)skb->data + K` far outside any packet buffer and can copy the results into a BPF map or the packet, giving an out-of-bounds kernel memory read primitive.\nI:H - `may_access_direct_pkt_data()` grants direct packet writes to SCHED_CLS, SCHED_ACT, XDP, LWT_XMIT and SK_SKB, so the same corrupted pointer yields kernel-mode stores at an attacker-influenced address \u2014 memory corruption exploitable for further escalation.\nA:H - syzbot reported this as a kernel crash; dereferencing the mangled address from softirq/NAPI context produces a page fault or general protection fault in kernel mode, oopsing or panicking the machine."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "4b48228eebce2ab1b01e3133da822164472b7e46", "versionType": "git"}, {"status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "f1620c93a1ec950d87ef327a565d3907736d3340", "versionType": "git"}, {"status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "f09757fe97a225ae505886eac572e4cbfba96537", "versionType": "git"}, {"status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "lessThan": "92de36080c93296ef9005690705cba260b9bd68a", "versionType": "git"}], "programFiles": ["include/linux/bpf.h", "kernel/bpf/verifier.c", "net/core/filter.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.6"}, {"status": "unaffected", "version": "0", "lessThan": "6.6", "versionType": "semver"}, {"status": "unaffected", "version": "6.6.158", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.10.13", "versionType": "semver", "lessThanOrEqual": "6.10.*"}, {"status": "unaffected", "version": "6.11.2", "versionType": "semver", "lessThanOrEqual": "6.11.*"}, {"status": "unaffected", "version": "6.12", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["include/linux/bpf.h", "kernel/bpf/verifier.c", "net/core/filter.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/4b48228eebce2ab1b01e3133da822164472b7e46"}, {"url": "https://git.kernel.org/stable/c/f1620c93a1ec950d87ef327a565d3907736d3340"}, {"url": "https://git.kernel.org/stable/c/f09757fe97a225ae505886eac572e4cbfba96537"}, {"url": "https://git.kernel.org/stable/c/92de36080c93296ef9005690705cba260b9bd68a"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fail verification for sign-extension of packet data/data_end/data_meta\n\nsyzbot reported a kernel crash due to\n commit 1f1e864b6555 (\"bpf: Handle sign-extenstin ctx member accesses\").\nThe reason is due to sign-extension of 32-bit load for\npacket data/data_end/data_meta uapi field.\n\nThe original code looks like:\n r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\n r3 = *(u32 *)(r1 + 80) /* load __sk_buff->data_end */\n r0 = r2\n r0 += 8\n if r3 > r0 goto +1\n ...\nNote that __sk_buff->data load has 32-bit sign extension.\n\nAfter verification and convert_ctx_accesses(), the final asm code looks like:\n r2 = *(u64 *)(r1 +208)\n r2 = (s32)r2\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\n ...\nNote that 'r2 = (s32)r2' may make the kernel __sk_buff->data address invalid\nwhich may cause runtime failure.\n\nCurrently, in C code, typically we have\n void *data = (void *)(long)skb->data;\n void *data_end = (void *)(long)skb->data_end;\n ...\nand it will generate\n r2 = *(u64 *)(r1 +208)\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\n\nIf we allow sign-extension,\n void *data = (void *)(long)(int)skb->data;\n void *data_end = (void *)(long)skb->data_end;\n ...\nthe generated code looks like\n r2 = *(u64 *)(r1 +208)\n r2 <<= 32\n r2 s>>= 32\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\nand this will cause verification failure since \"r2 <<= 32\" is not allowed\nas \"r2\" is a packet pointer.\n\nTo fix this issue for case\n r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\nthis patch added additional checking in is_valid_access() callback\nfunction for packet data/data_end/data_meta access. If those accesses\nare with sign-extenstion, the verification will fail.\n\n [1] https://lore.kernel.org/bpf/000000000000c90eee061d236d37@google.com/"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.158", "versionStartIncluding": "6.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.10.13", "versionStartIncluding": "6.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.11.2", "versionStartIncluding": "6.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12", "versionStartIncluding": "6.6"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-03T10:55:18.539Z"}}}, "cveMetadata": {"cveId": "CVE-2024-47702", "state": "PUBLISHED", "dateUpdated": "2026-10-03T10:55:18.539Z", "dateReserved": "2024-09-30T16:00:12.945Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-10-21T11:53:37.958Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["include/linux/bpf.h", "kernel/bpf/verifier.c", "net/core/filter.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "4b48228eebce2ab1b01e3133da822164472b7e46", "status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "versionType": "git"}, {"lessThan": "f1620c93a1ec950d87ef327a565d3907736d3340", "status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "versionType": "git"}, {"lessThan": "f09757fe97a225ae505886eac572e4cbfba96537", "status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "versionType": "git"}, {"lessThan": "92de36080c93296ef9005690705cba260b9bd68a", "status": "affected", "version": "1f1e864b65554e33fe74e3377e58b12f4302f2eb", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["include/linux/bpf.h", "kernel/bpf/verifier.c", "net/core/filter.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.6"}, {"lessThan": "6.6", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.158", "versionType": "semver"}, {"lessThanOrEqual": "6.10.*", "status": "unaffected", "version": "6.10.13", "versionType": "semver"}, {"lessThanOrEqual": "6.11.*", "status": "unaffected", "version": "6.11.2", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.12", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "5E608BB9-C140-4A10-AE7A-FC5B5D4C1972", "versionEndExcluding": "6.10.13", "versionStartIncluding": "6.6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "AB755D26-97F4-43B6-8604-CD076811E181", "versionEndExcluding": "6.11.2", "versionStartIncluding": "6.11", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fail verification for sign-extension of packet data/data_end/data_meta\n\nsyzbot reported a kernel crash due to\n commit 1f1e864b6555 (\"bpf: Handle sign-extenstin ctx member accesses\").\nThe reason is due to sign-extension of 32-bit load for\npacket data/data_end/data_meta uapi field.\n\nThe original code looks like:\n r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\n r3 = *(u32 *)(r1 + 80) /* load __sk_buff->data_end */\n r0 = r2\n r0 += 8\n if r3 > r0 goto +1\n ...\nNote that __sk_buff->data load has 32-bit sign extension.\n\nAfter verification and convert_ctx_accesses(), the final asm code looks like:\n r2 = *(u64 *)(r1 +208)\n r2 = (s32)r2\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\n ...\nNote that 'r2 = (s32)r2' may make the kernel __sk_buff->data address invalid\nwhich may cause runtime failure.\n\nCurrently, in C code, typically we have\n void *data = (void *)(long)skb->data;\n void *data_end = (void *)(long)skb->data_end;\n ...\nand it will generate\n r2 = *(u64 *)(r1 +208)\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\n\nIf we allow sign-extension,\n void *data = (void *)(long)(int)skb->data;\n void *data_end = (void *)(long)skb->data_end;\n ...\nthe generated code looks like\n r2 = *(u64 *)(r1 +208)\n r2 <<= 32\n r2 s>>= 32\n r3 = *(u64 *)(r1 +80)\n r0 = r2\n r0 += 8\n if r3 > r0 goto pc+1\nand this will cause verification failure since \"r2 <<= 32\" is not allowed\nas \"r2\" is a packet pointer.\n\nTo fix this issue for case\n r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\nthis patch added additional checking in is_valid_access() callback\nfunction for packet data/data_end/data_meta access. If those accesses\nare with sign-extenstion, the verification will fail.\n\n [1] https://lore.kernel.org/bpf/000000000000c90eee061d236d37@google.com/"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bpf: Error en la verificaci\u00f3n de la extensi\u00f3n de signo del paquete data/data_end/data_meta syzbot inform\u00f3 de un fallo del kernel debido a el commit 1f1e864b6555 (\"bpf: Manejar los accesos a miembros ctx de la extensi\u00f3n de signo\"). La raz\u00f3n se debe a la extensi\u00f3n de signo de la carga de 32 bits para el campo uapi del paquete data/data_end/data_meta. El c\u00f3digo original se ve as\u00ed: r2 = *(s32 *)(r1 + 76) /* load __sk_buff-&gt;data */ r3 = *(u32 *)(r1 + 80) /* load __sk_buff-&gt;data_end */ r0 = r2 r0 += 8 if r3 &gt; r0 goto +1 ... Tenga en cuenta que la carga de __sk_buff-&gt;data tiene una extensi\u00f3n de signo de 32 bits. Despu\u00e9s de la verificaci\u00f3n y convert_ctx_accesses(), el c\u00f3digo asm final se ve as\u00ed: r2 = *(u64 *)(r1 +208) r2 = (s32)r2 r3 = *(u64 *)(r1 +80) r0 = r2 r0 += 8 if r3 &gt; r0 goto pc+1 ... Tenga en cuenta que 'r2 = (s32)r2' puede hacer que la direcci\u00f3n __sk_buff-&gt;data del n\u00facleo sea inv\u00e1lida, lo que puede causar un error en tiempo de ejecuci\u00f3n. Actualmente, en el c\u00f3digo C, normalmente tenemos void *data = (void *)(long)skb-&gt;data; void *data_end = (void *)(long)skb-&gt;data_end; ... y generar\u00e1 r2 = *(u64 *)(r1 +208) r3 = *(u64 *)(r1 +80) r0 = r2 r0 += 8 if r3 &gt; r0 goto pc+1 Si permitimos la extensi\u00f3n de signo, void *data = (void *)(long)(int)skb-&gt;data; void *data_end = (void *)(long)skb-&gt;data_end; ... el c\u00f3digo generado se ve as\u00ed r2 = *(u64 *)(r1 +208) r2 &lt;&lt;= 32 r2 s&gt;&gt;= 32 r3 = *(u64 *)(r1 +80) r0 = r2 r0 += 8 if r3 &gt; r0 goto pc+1 y esto causar\u00e1 un error de verificaci\u00f3n ya que \"r2 &lt;&lt;= 32\" no est\u00e1 permitido ya que \"r2\" es un puntero de paquete. Para solucionar este problema en el caso r2 = *(s32 *)(r1 + 76) /* load __sk_buff-&gt;data */, este parche agreg\u00f3 una verificaci\u00f3n adicional en la funci\u00f3n de devoluci\u00f3n de llamada is_valid_access() para el acceso a los paquetes data/data_end/data_meta. Si esos accesos son con la extensi\u00f3n sign-extenstion, la verificaci\u00f3n fallar\u00e1. [1] https://lore.kernel.org/bpf/000000000000c90eee061d236d37@google.com/"}], "id": "CVE-2024-47702", "lastModified": "2026-10-03T11:17:31.513", "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"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2024-47702", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2024-10-21T13:04:24.861686Z", "version": "2.0.3"}}]}, "published": "2024-10-21T12:15:06.743", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4b48228eebce2ab1b01e3133da822164472b7e46"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/92de36080c93296ef9005690705cba260b9bd68a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f09757fe97a225ae505886eac572e4cbfba96537"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f1620c93a1ec950d87ef327a565d3907736d3340"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: bpf: Fail verification for sign-extension of packet data/data_end/data_meta", "id": "2320179", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2320179"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.4", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-190", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbpf: Fail verification for sign-extension of packet data/data_end/data_meta\nsyzbot reported a kernel crash due to\ncommit 1f1e864b6555 (\"bpf: Handle sign-extenstin ctx member accesses\").\nThe reason is due to sign-extension of 32-bit load for\npacket data/data_end/data_meta uapi field.\nThe original code looks like:\nr2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\nr3 = *(u32 *)(r1 + 80) /* load __sk_buff->data_end */\nr0 = r2\nr0 += 8\nif r3 > r0 goto +1\n...\nNote that __sk_buff->data load has 32-bit sign extension.\nAfter verification and convert_ctx_accesses(), the final asm code looks like:\nr2 = *(u64 *)(r1 +208)\nr2 = (s32)r2\nr3 = *(u64 *)(r1 +80)\nr0 = r2\nr0 += 8\nif r3 > r0 goto pc+1\n...\nNote that 'r2 = (s32)r2' may make the kernel __sk_buff->data address invalid\nwhich may cause runtime failure.\nCurrently, in C code, typically we have\nvoid *data = (void *)(long)skb->data;\nvoid *data_end = (void *)(long)skb->data_end;\n...\nand it will generate\nr2 = *(u64 *)(r1 +208)\nr3 = *(u64 *)(r1 +80)\nr0 = r2\nr0 += 8\nif r3 > r0 goto pc+1\nIf we allow sign-extension,\nvoid *data = (void *)(long)(int)skb->data;\nvoid *data_end = (void *)(long)skb->data_end;\n...\nthe generated code looks like\nr2 = *(u64 *)(r1 +208)\nr2 <<= 32\nr2 s>>= 32\nr3 = *(u64 *)(r1 +80)\nr0 = r2\nr0 += 8\nif r3 > r0 goto pc+1\nand this will cause verification failure since \"r2 <<= 32\" is not allowed\nas \"r2\" is a packet pointer.\nTo fix this issue for case\nr2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */\nthis patch added additional checking in is_valid_access() callback\nfunction for packet data/data_end/data_meta access. If those accesses\nare with sign-extenstion, the verification will fail.\n[1] https://lore.kernel.org/bpf/000000000000c90eee061d236d37@google.com/"], "name": "CVE-2024-47702", "package_state": [{"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": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "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": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-10-21T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2024-47702\nhttps://nvd.nist.gov/vuln/detail/CVE-2024-47702\nhttps://lore.kernel.org/linux-cve-announce/2024102115-CVE-2024-47702-c5c4@gregkh/T"], "statement": "The default Red Hat Enterprise Linux kernel prevents unprivileged users from being able to use eBPF by the kernel.unprivileged_bpf_disabled sysctl. This would require a privileged user with CAP_SYS_ADMIN or root to be able to abuse this flaw reducing its attack space.", "threat_severity": "Low"}

{}