CVE-2022-48762

{"id": "CVE-2022-48762", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.2, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 2.5}]}, "published": "2024-06-20T12:15:14.287", "references": [{"url": "https://git.kernel.org/stable/c/3758a6c74e08bdc15ccccd6872a6ad37d165239a", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/47fe7a1c5e3e011eeb4ab79f2d54a794fdd1c3eb", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3758a6c74e08bdc15ccccd6872a6ad37d165239a", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/47fe7a1c5e3e011eeb4ab79f2d54a794fdd1c3eb", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\narm64: extable: fix load_unaligned_zeropad() reg indices\n\nIn ex_handler_load_unaligned_zeropad() we erroneously extract the data and\naddr register indices from ex->type rather than ex->data. As ex->type will\ncontain EX_TYPE_LOAD_UNALIGNED_ZEROPAD (i.e. 4):\n * We'll always treat X0 as the address register, since EX_DATA_REG_ADDR is\n extracted from bits [9:5]. Thus, we may attempt to dereference an\n arbitrary address as X0 may hold an arbitrary value.\n * We'll always treat X4 as the data register, since EX_DATA_REG_DATA is\n extracted from bits [4:0]. Thus we will corrupt X4 and cause arbitrary\n behaviour within load_unaligned_zeropad() and its caller.\n\nFix this by extracting both values from ex->data as originally intended.\n\nOn an MTE-enabled QEMU image we are hitting the following crash:\n Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000\n Call trace:\n fixup_exception+0xc4/0x108\n __do_kernel_fault+0x3c/0x268\n do_tag_check_fault+0x3c/0x104\n do_mem_abort+0x44/0xf4\n el1_abort+0x40/0x64\n el1h_64_sync_handler+0x60/0xa0\n el1h_64_sync+0x7c/0x80\n link_path_walk+0x150/0x344\n path_openat+0xa0/0x7dc\n do_filp_open+0xb8/0x168\n do_sys_openat2+0x88/0x17c\n __arm64_sys_openat+0x74/0xa0\n invoke_syscall+0x48/0x148\n el0_svc_common+0xb8/0xf8\n do_el0_svc+0x28/0x88\n el0_svc+0x24/0x84\n el0t_64_sync_handler+0x88/0xec\n el0t_64_sync+0x1b4/0x1b8\n Code: f8695a69 71007d1f 540000e0 927df12a (f940014a)"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: arm64: extable: corrige los \u00edndices de registro load_unaligned_zeropad() En ex_handler_load_unaligned_zeropad() extraemos err\u00f3neamente los datos y los \u00edndices de registro de direcciones de ex->type en lugar de ex->data. Como ex->type contendr\u00e1 EX_TYPE_LOAD_UNALIGNED_ZEROPAD (es decir, 4): * Siempre trataremos a X0 como el registro de direcci\u00f3n, ya que EX_DATA_REG_ADDR se extrae de los bits [9:5]. Por lo tanto, podemos intentar eliminar la referencia a una direcci\u00f3n arbitraria ya que X0 puede tener un valor arbitrario. * Siempre trataremos a X4 como el registro de datos, ya que EX_DATA_REG_DATA se extrae de los bits [4:0]. Por lo tanto, corromperemos X4 y provocaremos un comportamiento arbitrario dentro de load_unaligned_zeropad() y su llamador. Solucione este problema extrayendo ambos valores de ex->data como se pretend\u00eda originalmente. En una imagen QEMU habilitada para MTE, nos encontramos con el siguiente bloqueo: No se puede manejar la desreferencia del puntero NULL del kernel en la direcci\u00f3n virtual 0000000000000000 Rastreo de llamadas: fixup_exception+0xc4/0x108 __do_kernel_fault+0x3c/0x268 do_tag_check_fault+0x3c/0x104 do_mem_abort+0x44/0 xf4 el1_abort+ 0x40/0x64 el1h_64_sync_handler+0x60/0xa0 el1h_64_sync+0x7c/0x80 link_path_walk+0x150/0x344 path_openat+0xa0/0x7dc do_filp_open+0xb8/0x168 do_sys_openat2+0x88/0x17c __arm64_s ys_openat+0x74/0xa0 invoke_syscall+0x48/0x148 el0_svc_common+0xb8/0xf8 do_el0_svc+ 0x28/0x88 el0_svc+0x24/0x84 el0t_64_sync_handler+0x88/0xec el0t_64_sync+0x1b4/0x1b8 C\u00f3digo: f8695a69 71007d1f 540000e0 927df12a (f940014a)"}], "lastModified": "2025-03-24T18:17:02.420", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1AD9E77E-B27E-450C-8FD8-B64EC5FB002D", "versionEndExcluding": "5.16.5", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.17:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7BD5F8D9-54FA-4CB0-B4F0-CB0471FDDB2D"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}