{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72196", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.911Z", "datePublished": "2026-08-15T05:53:55.509Z", "dateUpdated": "2026-08-17T05:41:23.012Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:41:23.012Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: bound copy_lcns dp->page_lcns[] index in analysis pass\n\nIn log_replay()'s analysis pass, after find_dp() returns a\nvalid DIR_PAGE_ENTRY for the (target_attr, target_vcn) tuple,\nthe copy_lcns block walks lrh->lcns_follow further entries:\n\n\tt16 = le16_to_cpu(lrh->lcns_follow);\n\tfor (i = 0; i < t16; i++) {\n\t size_t j = (size_t)(le64_to_cpu(lrh->target_vcn) -\n\t le64_to_cpu(dp->vcn));\n\t dp->page_lcns[j + i] = lrh->page_lcns[i];\n\t}\n\nfind_dp() only validates that target_vcn falls within\n[dp->vcn, dp->vcn + dp->lcns_follow), i.e., that the FIRST\ncluster is covered. The walk through the further entries is\nnot bounded against dp->lcns_follow. For a malformed LRH\nwhere target_vcn = dp->vcn + dp->lcns_follow - 1 and\nlrh->lcns_follow > 1, the i > 0 writes overflow the dp's\nallocated page_lcns[] array.\n\nAdd the missing j + lrh->lcns_follow <= dp->lcns_follow guard.\n\nReproduced under UML+KASAN on mainline 8d90b09e6741 as a\nslab-out-of-bounds write of size 8 from log_replay+0x68d4 on\nthe mount path.\n\nThis is distinct from Pavitra Jha's 2026-05-02 patch\n(\"fs/ntfs3: validate lcns_follow in log_replay conversion\",\n<20260502154252.164586-1-jhapavitra98@gmail.com>) which\naddresses the separate version-0 dirty-page-table conversion\npath's memmove(&dp->vcn, ...) call. The two fixes are\ncomplementary; both should land.\n\n[almaz.alexandrovich@paragon-software.com: clang-formatted the changes,\nfixed conflicts]" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.4, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The flaw is in ntfs3 log_replay() during mount when parsing a crafted $LogFile on a block device; exploitation requires a local mount syscall or auto-mount of attacker-supplied removable media, not delivery through a network-facing kernel protocol handler.\nAC:L - An attacker fully controls malicious NTFS $LogFile journal fields (target_vcn, lcns_follow, page_lcns) and can craft the dirty-page-table state; KASAN reliably reproduced the slab OOB write on mount with no races or attacker-uncontrollable conditions.\nPR:N - No account or privileges on the victim are needed when a crafted NTFS volume on removable media is auto-mounted by udisks/systemd as root; alternatively an unprivileged user can trigger replay via user-namespace mount with CAP_SYS_ADMIN.\nUI:N - Once an attacker mounts or causes mount of a crafted NTFS image, log_replay() runs automatically inside ntfs_fill_super() with no further user interaction; the vulnerable copy_lcns path is reached during standard journal analysis on every affected mount attempt.\nS:U - Exploitation corrupts kernel heap memory during ntfs3 journal replay in the mounting process context; impact is privilege escalation within the same kernel/host security boundary, not a VM-guest-to-host or IOMMU boundary crossing.\nC:H - KASAN confirmed a slab out-of-bounds write of 8 bytes past dp->page_lcns[] in a kmalloc-backed DIR_PAGE_ENTRY; such heap corruption can overwrite adjacent slab objects and be groomed into arbitrary kernel memory read primitives.\nI:H - The bug is an out-of-bounds write into kernel heap metadata or adjacent objects beyond the allocated page_lcns[] array; per kernel guidance OOB writes enable controlled heap corruption paths toward arbitrary kernel writes and privilege escalation.\nA:H - KASAN reported slab-out-of-bounds write from log_replay() on mount; heap corruption during journal replay can cause immediate kernel oops/panic and is repeatable on each mount of a malicious NTFS volume, constituting high availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ntfs3/fslog.c" ], "versions": [ { "version": "b46acd6a6a627d876898e1c84d3f84902264b445", "lessThan": "9b3d8cc9d54fcded4de51b2b1026ae7182512077", "status": "affected", "versionType": "git" }, { "version": "b46acd6a6a627d876898e1c84d3f84902264b445", "lessThan": "9b7c28d8c61bdb041936222a09a708531a1c2921", "status": "affected", "versionType": "git" }, { "version": "b46acd6a6a627d876898e1c84d3f84902264b445", "lessThan": "0f13e823bf86bd1800168ea0bb5bca8b8500a81c", "status": "affected", "versionType": "git" }, { "version": "b46acd6a6a627d876898e1c84d3f84902264b445", "lessThan": "d240cd98f5f7b65c90f6b2b6abe3232ccdc405ab", "status": "affected", "versionType": "git" }, { "version": "b46acd6a6a627d876898e1c84d3f84902264b445", "lessThan": "49c86dae0c0ccb8d98ddcdc46987259389c816dd", "status": "affected", "versionType": "git" }, { "version": "b46acd6a6a627d876898e1c84d3f84902264b445", "lessThan": "5e7b598660cfa8e5af172cf4c65cffc126333307", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ntfs3/fslog.c" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "5.15", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/9b3d8cc9d54fcded4de51b2b1026ae7182512077" }, { "url": "https://git.kernel.org/stable/c/9b7c28d8c61bdb041936222a09a708531a1c2921" }, { "url": "https://git.kernel.org/stable/c/0f13e823bf86bd1800168ea0bb5bca8b8500a81c" }, { "url": "https://git.kernel.org/stable/c/d240cd98f5f7b65c90f6b2b6abe3232ccdc405ab" }, { "url": "https://git.kernel.org/stable/c/49c86dae0c0ccb8d98ddcdc46987259389c816dd" }, { "url": "https://git.kernel.org/stable/c/5e7b598660cfa8e5af172cf4c65cffc126333307" } ], "title": "fs/ntfs3: bound copy_lcns dp->page_lcns[] index in analysis pass", "x_generator": { "engine": "bippy-1.2.0" } } } }