{"id":"CVE-2026-89616","state":"PUBLISHED","title":"fs/ntfs3: fix info-leak on partial LZNT decompress in ni_read_frame()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: fix info-leak on partial LZNT decompress in ni_read_frame()\n\nni_read_frame() decompresses an LZNT $DATA frame into the vmapped target\npages and then trusts decompress_lznt()'s return value:\n\n  unc_size = decompress_lznt(frame_ondisk, ondisk_size, frame_mem,\n                             frame_size);\n  if ((ssize_t)unc_size < 0)        err = unc_size;\n  else if (!unc_size || unc_size > frame_size)  err = -EINVAL;\n\ndecompress_lznt() stops as soon as the compressed stream is exhausted\n(e.g. a zero chunk header) and returns the number of bytes it actually\nwrote, which may be far less than frame_size. The bytes between unc_size\nand frame_size are never written. The only memset() that follows zeroes\nthe region beyond i_valid; when the frame lies entirely within the file's\nvalid size that memset() does not run, so the gap retains whatever was in\nthe just-vmapped pages. All pages are then marked uptodate and returned\nto userspace, disclosing uninitialized (recently-freed) kernel page\nmemory. A crafted compressed file whose stream decompresses to only a few\nbytes leaks the remainder of every frame on a plain read(2), which is\nenough to recover kernel pointers and defeat KASLR.\n\nZero the [unc_size, frame_size) tail immediately after a successful LZNT\ndecompress so the remainder reads back as zero.","publishedAt":"2026-09-11T19:45:16.064Z","updatedAt":"2026-10-19T08:49:48.800Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"7d60a4c49af4d5cb88aa7cbf998d0408bd415055","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"cd40eee4923d104ebec9ac7513b971bc441e431d","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"77d8efd04745cda23858546afdbd9d07b591758e","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"0f699ddb290a24b37e1bc9bf1e3c9dbccf564bea","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"376ee45659a4b943df672ad275c63da00655f929","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"4a1b39b2e10eb8de86265e80cf2be4396bc1dce4","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"35d1ea92c7d946e2ebdbe36cdb2c969c8704bebd","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs3/frecord.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.109","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs3/frecord.c"]}],"references":["https://git.kernel.org/stable/c/7d60a4c49af4d5cb88aa7cbf998d0408bd415055","https://git.kernel.org/stable/c/cd40eee4923d104ebec9ac7513b971bc441e431d","https://git.kernel.org/stable/c/77d8efd04745cda23858546afdbd9d07b591758e","https://git.kernel.org/stable/c/0f699ddb290a24b37e1bc9bf1e3c9dbccf564bea","https://git.kernel.org/stable/c/376ee45659a4b943df672ad275c63da00655f929","https://git.kernel.org/stable/c/4a1b39b2e10eb8de86265e80cf2be4396bc1dce4","https://git.kernel.org/stable/c/35d1ea92c7d946e2ebdbe36cdb2c969c8704bebd"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89616.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89616","state":"PUBLISHED","datePublished":"2026-09-11T19:45:16.064Z","dateUpdated":"2026-10-19T08:49:48.800Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.735Z"},"containers":{"cna":{"title":"fs/ntfs3: fix info-leak on partial LZNT decompress in ni_read_frame()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nfs/ntfs3: fix info-leak on partial LZNT decompress in ni_read_frame()\n\nni_read_frame() decompresses an LZNT $DATA frame into the vmapped target\npages and then trusts decompress_lznt()'s return value:\n\n  unc_size = decompress_lznt(frame_ondisk, ondisk_size, frame_mem,\n                             frame_size);\n  if ((ssize_t)unc_size < 0)        err = unc_size;\n  else if (!unc_size || unc_size > frame_size)  err = -EINVAL;\n\ndecompress_lznt() stops as soon as the compressed stream is exhausted\n(e.g. a zero chunk header) and returns the number of bytes it actually\nwrote, which may be far less than frame_size. The bytes between unc_size\nand frame_size are never written. The only memset() that follows zeroes\nthe region beyond i_valid; when the frame lies entirely within the file's\nvalid size that memset() does not run, so the gap retains whatever was in\nthe just-vmapped pages. All pages are then marked uptodate and returned\nto userspace, disclosing uninitialized (recently-freed) kernel page\nmemory. A crafted compressed file whose stream decompresses to only a few\nbytes leaks the remainder of every frame on a plain read(2), which is\nenough to recover kernel pointers and defeat KASLR.\n\nZero the [unc_size, frame_size) tail immediately after a successful LZNT\ndecompress so the remainder reads back as zero."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"7d60a4c49af4d5cb88aa7cbf998d0408bd415055","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"cd40eee4923d104ebec9ac7513b971bc441e431d","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"77d8efd04745cda23858546afdbd9d07b591758e","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"0f699ddb290a24b37e1bc9bf1e3c9dbccf564bea","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"376ee45659a4b943df672ad275c63da00655f929","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"4a1b39b2e10eb8de86265e80cf2be4396bc1dce4","versionType":"git"},{"version":"4342306f0f0d5ff4315a204d315c1b51b914fca5","status":"affected","lessThan":"35d1ea92c7d946e2ebdbe36cdb2c969c8704bebd","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs3/frecord.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.109","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.50","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.4","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs3/frecord.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7d60a4c49af4d5cb88aa7cbf998d0408bd415055"},{"url":"https://git.kernel.org/stable/c/cd40eee4923d104ebec9ac7513b971bc441e431d"},{"url":"https://git.kernel.org/stable/c/77d8efd04745cda23858546afdbd9d07b591758e"},{"url":"https://git.kernel.org/stable/c/0f699ddb290a24b37e1bc9bf1e3c9dbccf564bea"},{"url":"https://git.kernel.org/stable/c/376ee45659a4b943df672ad275c63da00655f929"},{"url":"https://git.kernel.org/stable/c/4a1b39b2e10eb8de86265e80cf2be4396bc1dce4"},{"url":"https://git.kernel.org/stable/c/35d1ea92c7d946e2ebdbe36cdb2c969c8704bebd"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - ni_read_frame() runs from ntfs_read_folio on LZNT-compressed reads. ntfs3 registers export_operations, so ksmbd/nfsd vfs_read and splice on an exported NTFS volume reach this path and return leaked page-cache bytes to a remote SMB/NFS client on NAS and hybrid file-server deployments.\nAC:L - A crafted NTFS image fully controls the on-disk LZNT stream; a zero chunk header makes decompress_lznt() return far fewer than frame_size bytes deterministically, with no race, rare config, or attacker-uncontrollable memory layout required.\nPR:N - A remote client can trigger the leak by reading a world-readable compressed file over NFS (AUTH_SYS/guest) or a ksmbd guest share with no local account or capability on the host; ntfs3 file-read paths check only inode state, not privileges.\nUI:N - After the NTFS volume is mounted and exported—the normal state for NAS, dual-boot, and automounted removable NTFS—the attacker only issues reads; no further victim action such as opening a file or confirming a prompt is required.\nS:U - The leak exposes the host kernel's own freed page contents through that kernel's page cache to the reader and does not cross a VM, guest-to-host, IOMMU, or other security-authority boundary.\nC:H - Each crafted frame can disclose up to the uncompressed LZNT unit (typically 64KiB) of uninitialized recently-freed kernel page memory, repeatable across the file, including kernel pointers for KASLR bypass and residual secrets rather than a small bounded read.\nI:N - The defect only leaves the decompressed-frame tail unzeroed in the file's own page-cache pages; it does not perform an out-of-bounds write, corrupt kernel objects, or yield a write or control-flow hijack primitive.\nA:N - Partial LZNT decompress is treated as success; pages are marked uptodate and the read returns data without a kernel oops, panic, hang, deadlock, or other availability loss."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:49:48.800Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.12.109"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.18.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}