{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-48762","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-06-20T11:09:39.060Z","datePublished":"2024-06-20T11:13:39.855Z","dateUpdated":"2026-08-05T08:52:11.000Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T08:52:11.000Z"},"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)"}],"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 bug is in the arm64 exception fixup for load_unaligned_zeropad(), reached when pathname hashing faults during local syscalls such as openat→link_path_walk→hash_name; it is not a network-protocol entry point.\nAC:L - On the worst reasonable deployment (MTE-enabled arm64, e.g. Android), an unprivileged attacker can craft a pathname so word-at-a-time hashing crosses a tag/allocation boundary and reliably invokes the broken fixup, with no attacker-uncontrollable race.\nPR:L - Triggering requires only an unprivileged local account able to call open/stat-style path lookups; no capabilities or init-namespace root are needed.\nUI:N - The attacker invokes the vulnerable path themselves via ordinary filesystem syscalls; no separate victim action is required.\nS:U - Impact is confined to the host kernel’s own privilege domain (oops or corrupted kernel register state during path walk); this is not a VM/IOMMU/sandbox boundary escape.\nC:H - The broken handler always dereferences X0 and loads an unsigned long from that address, so a non-NULL X0 yields an unintended kernel memory read; combined with X4 clobber this is a memory-safety read primitive scored as C:H.\nI:H - The handler always writes the loaded value into X4, and the fix commit explicitly notes this corrupts X4 and causes arbitrary behaviour in load_unaligned_zeropad() and its caller, which can turn corrupted pointer/state into integrity compromise.\nA:H - When X0 is NULL (common after may_lookup in link_path_walk), the fixup’s own load is a NULL deref that nests into die_kernel_fault, producing a documented kernel oops/panic."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/mm/extable.c"],"versions":[{"version":"753b32368705c396000f95f33c3b7018474e33ad","lessThan":"47fe7a1c5e3e011eeb4ab79f2d54a794fdd1c3eb","status":"affected","versionType":"git"},{"version":"753b32368705c396000f95f33c3b7018474e33ad","lessThan":"3758a6c74e08bdc15ccccd6872a6ad37d165239a","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/mm/extable.c"],"versions":[{"version":"5.16","status":"affected"},{"version":"0","lessThan":"5.16","status":"unaffected","versionType":"semver"},{"version":"5.16.5","lessThanOrEqual":"5.16.*","status":"unaffected","versionType":"semver"},{"version":"5.17","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":"5.16","versionEndExcluding":"5.16.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"5.17"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/47fe7a1c5e3e011eeb4ab79f2d54a794fdd1c3eb"},{"url":"https://git.kernel.org/stable/c/3758a6c74e08bdc15ccccd6872a6ad37d165239a"}],"title":"arm64: extable: fix load_unaligned_zeropad() reg indices","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"problemTypes":[{"descriptions":[{"type":"CWE","lang":"en","description":"CWE-noinfo Not enough information"}]}],"metrics":[{"cvssV3_1":{"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"}},{"other":{"type":"ssvc","content":{"timestamp":"2024-06-20T13:32:18.518076Z","id":"CVE-2022-48762","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-10-29T18:16:31.076Z"}},{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-03T15:25:01.535Z"},"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/47fe7a1c5e3e011eeb4ab79f2d54a794fdd1c3eb","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/3758a6c74e08bdc15ccccd6872a6ad37d165239a","tags":["x_transferred"]}]}]}}