{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-42233", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-07-30T07:40:12.251Z", "datePublished": "2024-08-07T15:14:23.858Z", "dateUpdated": "2026-08-05T11:35:58.248Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:35:58.248Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfilemap: replace pte_offset_map() with pte_offset_map_nolock()\n\nThe vmf->ptl in filemap_fault_recheck_pte_none() is still set from\nhandle_pte_fault(). But at the same time, we did a pte_unmap(vmf->pte). \nAfter a pte_unmap(vmf->pte) unmap and rcu_read_unlock(), the page table\nmay be racily changed and vmf->ptl maybe fails to protect the actual page\ntable. Fix this by replacing pte_offset_map() with\npte_offset_map_nolock().\n\nAs David said, the PTL pointer might be stale so if we continue to use\nit infilemap_fault_recheck_pte_none(), it might trigger UAF. Also, if\nthe PTL fails, the issue fixed by commit 58f327f2ce80 (\"filemap: avoid\nunnecessary major faults in filemap_fault()\") might reappear." } ], "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 triggered by a normal page fault on a locally mmap'ed file, reached through mmap/mlock2/madvise syscalls by a process on the machine. There is no network-facing path to `filemap_fault()`.\nAC:L - Although a race is involved, the attacker owns both sides of it: one thread faults on its own mlocked, page-cache-cold file mapping while another unprivileged thread issues `MADV_COLLAPSE`, and both only need `mmap_lock` read so they run concurrently. All preconditions (VM_LOCKED, pte_none, page-cache miss, page-table collapse) are set up deterministically by the attacker and the attempt can be retried in a tight loop.\nPR:L - Only an ordinary unprivileged local user account is required — `can_do_mlock()` passes on the default nonzero RLIMIT_MEMLOCK with no capability, and `MADV_COLLAPSE` requires no privilege. No root, no CAP_* and no namespace tricks are needed.\nUI:N - The attacker's own threads perform every step — mapping and locking a file, faulting on it, and collapsing the page table. No victim action or interaction is involved.\nS:U - The use-after-free corrupts kernel memory within the same kernel security authority; there is no crossing of a VM, IOMMU, or other security-authority boundary.\nC:H - This is a use-after-free on the split page-table lock: `spin_lock()`/`spin_unlock()` read a freed object that the attacker can have reallocated with sprayed content, and the resulting slab/`struct page` metadata corruption (overlapping allocations) is a well-known route to arbitrary kernel memory disclosure.\nI:H - Taking the stale lock writes into freed memory — either a reallocated `kmem_cache` object (ALLOC_SPLIT_PTLOCKS) or word 5 of a reused `struct page`, which aliases `struct slab::counters` (inuse/objects/frozen) and `page->private`. Corrupting slab metadata yields overlapping object allocations and a path to arbitrary write and control-flow hijack.\nA:H - A use-after-free on a spinlock reliably produces oopses, slab corruption panics, and deadlocks/hangs when the freed lock word is reused and never released. Any unprivileged user can trigger it repeatedly to crash the system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/filemap.c" ], "versions": [ { "version": "58f327f2ce80f9c7b4a70e9cf017ae8810d44a20", "lessThan": "6a6c2aec1a89506595801b4cf7e8eef035f33748", "status": "affected", "versionType": "git" }, { "version": "58f327f2ce80f9c7b4a70e9cf017ae8810d44a20", "lessThan": "24be02a42181f0707be0498045c4c4b13273b16d", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "mm/filemap.c" ], "versions": [ { "version": "6.9", "status": "affected" }, { "version": "0", "lessThan": "6.9", "status": "unaffected", "versionType": "semver" }, { "version": "6.9.10", "lessThanOrEqual": "6.9.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.10", "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": "6.9", "versionEndExcluding": "6.9.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.10" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/6a6c2aec1a89506595801b4cf7e8eef035f33748" }, { "url": "https://git.kernel.org/stable/c/24be02a42181f0707be0498045c4c4b13273b16d" } ], "title": "filemap: replace pte_offset_map() with pte_offset_map_nolock()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-42233", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-09-10T16:14:13.816205Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-11T17:34:32.513Z" } } ] } }