{"id":"CVE-2026-72197","title":"fs/ntfs3: bound DeleteIndexEntryAllocation memmove length","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: bound DeleteIndexEntryAllocation memmove length\n\nIn do_action()'s DeleteIndexEntryAllocation case, e->size comes\nfrom an on-disk INDEX_BUFFER entry.  When e->…","severity":"high","cvss":8.4,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < c38ed2ab62fab75fd6d0fdc2bee540fbebc7b959","Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < b509b9613f20dc5b653d54bf78fab00d79cc43c8","Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 4c8aac931c1cd70347961ba5157aa916448c6a25","Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < f383aae59ec3994c14804f4191c59038b206be81","Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 09fddd52c1b0cef2c086d61be8f3d5dc92e36565","Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 554700c65d398276cb00a8ef95f1d5e00b9eff93","Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < fc4626bb3656362de8b0ecd56605d47a19ec3518","Linux 5.15"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T18:43:48.330736Z"},"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T18:45:01.720Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-72197","references":[{"url":"https://git.kernel.org/stable/c/c38ed2ab62fab75fd6d0fdc2bee540fbebc7b959"},{"url":"https://git.kernel.org/stable/c/b509b9613f20dc5b653d54bf78fab00d79cc43c8"},{"url":"https://git.kernel.org/stable/c/4c8aac931c1cd70347961ba5157aa916448c6a25"},{"url":"https://git.kernel.org/stable/c/f383aae59ec3994c14804f4191c59038b206be81"},{"url":"https://git.kernel.org/stable/c/09fddd52c1b0cef2c086d61be8f3d5dc92e36565"},{"url":"https://git.kernel.org/stable/c/554700c65d398276cb00a8ef95f1d5e00b9eff93"},{"url":"https://git.kernel.org/stable/c/fc4626bb3656362de8b0ecd56605d47a19ec3518"}],"tags":["cve.org"],"epss":0.00185,"epssPercentile":0.07565,"ingestedAt":"2026-10-16T19:46:24.422Z","slug":"CVE-2026-72197","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: bound DeleteIndexEntryAllocation memmove length\n\nIn do_action()'s DeleteIndexEntryAllocation case, e->size comes\nfrom an on-disk INDEX_BUFFER entry.  When e->size makes\ne + e->size point past hdr + hdr->used,\nPtrOffset(e1, Add2Ptr(hdr, used)) returns a negative ptrdiff_t\nthat is silently cast to a quasi-infinite size_t when passed\nto memmove().  The memmove then walks past the destination\nbuffer.\n\nThe sibling DeleteIndexEntryRoot case at fslog.c:3540-3543\nalready carries the corresponding guard:\n\n\tif (PtrOffset(e1, Add2Ptr(hdr, used)) < esize ||\n\t    Add2Ptr(e, esize) > Add2Ptr(lrh, rec_len) ||\n\t    used + esize > le32_to_cpu(hdr->total)) {\n\t\tgoto dirty_vol;\n\t}\n\nApply the same shape to the allocation-path case.  Also reject\nesize == 0: memmove(e, e, ...) is a no-op and leaves\nhdr->used unchanged, hiding a malformed entry from the\nexisting check_index_header() walk.\n\nReproduced under UML+KASAN on mainline 8d90b09e6741 by\nmounting a crafted NTFS image: the unguarded memmove takes a\nlength of 0xffffffffffffff00 and the kernel oopses in\nmemmove+0x81/0x1a0 on the do_action+0x36a2 frame.\n\n[almaz.alexandrovich@paragon-software.com: clang-formatted the changes]\n\n## Affected\n\n- `Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < c38ed2ab62fab75fd6d0fdc2bee540fbebc7b959`\n- `Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < b509b9613f20dc5b653d54bf78fab00d79cc43c8`\n- `Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 4c8aac931c1cd70347961ba5157aa916448c6a25`\n- `Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < f383aae59ec3994c14804f4191c59038b206be81`\n- `Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 09fddd52c1b0cef2c086d61be8f3d5dc92e36565`\n- `Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < 554700c65d398276cb00a8ef95f1d5e00b9eff93`\n- `Linux >= b46acd6a6a627d876898e1c84d3f84902264b445 < fc4626bb3656362de8b0ecd56605d47a19ec3518`\n- `Linux 5.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":46,"depthScoreParts":{"impact":46.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}