{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90118","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.787Z","datePublished":"2026-09-17T16:06:23.333Z","dateUpdated":"2026-09-18T17:53:07.562Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-18T17:53:07.562Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: fix off-by-one page overflow in ntfs_decompress()\n\nThe per-token range check in ntfs_decompress() uses\n\n\tif (cb >= cb_sb_end || dp_addr > dp_sb_end)\n\t\tbreak;\n\nso dp_addr == dp_sb_end falls through to the symbol copy\n`*dp_addr++ = *cb++`, writing one byte past the destination page.  Since\nNTFS_SB_SIZE == PAGE_SIZE the destination is a single page, so the byte\nlands in the adjacent page, and *dest_ofs is left one past the sub-block\nend (the later `*dest_ofs &= ~PAGE_MASK` then yields 1, not 0, so the page\nis never finalized and later sub-blocks keep writing further past it).  A\ncorrupted compressed $DATA attribute thus produces a bounded run of\nout-of-bounds writes when the file is read.\n\nBreak as soon as dp_addr reaches dp_sb_end; a full sub-block still\ncompletes, as its final copy advances dp_addr to exactly dp_sb_end."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The overflowing bytes are LZNT-style symbol tokens in a compressed unnamed $DATA attribute. They reach ntfs_decompress() only after ntfs_file_read_iter→generic_file_read_iter→ntfs_read_folio→ntfs_read_compressed_block() copies those clusters from the block device; a remote client does not carry the token stream.\nAC:L - A crafted compressed $DATA that leaves dp_addr==dp_sb_end makes the per-token `dp_addr > dp_sb_end` check fall through to `*dp_addr++ = *cb++`. Ending the sub-block so `*dest_ofs &= ~PAGE_MASK` yields 1 is deterministic and does not depend on a race or uninfluenced layout.\nPR:N - The attacker only needs to supply the image that contains the malformed compressed $DATA; ntfs_fs_type has no FS_USERNS_MOUNT so mount_capable() needs init-namespace CAP_SYS_ADMIN, which is the victim's mount (UI:R), not an attacker privilege on the target.\nUI:R - The malformed tokens exist only on the attacker-supplied volume. ntfs_get_tree()→get_tree_bdev()→ntfs_fill_super() must mount that image before ntfs_file_read_iter can read the compressed file and enter ntfs_decompress().\nS:U - The write past kmap_local_page() of dest_pages[] corrupts the host kernel's adjacent page in the same OS security domain; it is not a VM, IOMMU, or sandbox boundary crossing.\nC:H - The off-by-one `*dp_addr++ = *cb++` plus later sub-blocks (dest_ofs left at 1, so the dest folio is never finalized) overwrite the physically adjacent kernel page, a memory-corruption primitive that can be leveraged for kernel information disclosure.\nI:H - Each overflowing symbol token writes an attacker-chosen byte from the compressed stream one past the destination page, and later sub-blocks keep writing further past it into the adjacent page, an out-of-bounds kernel write usable for control-flow hijack.\nA:H - Writing past the kmap_local_page() mapping of the dest folio into the next pfn can oops or panic the kernel on the ntfs_file_read_iter→ntfs_decompress() path even when the overflow is not turned into a reliable write primitive."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ntfs/compress.c"],"versions":[{"version":"1e9ea7e04472d4e5e12e58c881eaacfb3e49b669","lessThan":"b42644e425fed4a5cd6c88372655da5c1b52c666","status":"affected","versionType":"git"},{"version":"1e9ea7e04472d4e5e12e58c881eaacfb3e49b669","lessThan":"98716c9fce21f6c8a9d71e08cf53e7504fa562f4","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/ntfs/compress.c"],"versions":[{"version":"7.1","status":"affected"},{"version":"0","lessThan":"7.1","status":"unaffected","versionType":"semver"},{"version":"7.2.6","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"7.1","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.1","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/b42644e425fed4a5cd6c88372655da5c1b52c666"},{"url":"https://git.kernel.org/stable/c/98716c9fce21f6c8a9d71e08cf53e7504fa562f4"}],"title":"ntfs: fix off-by-one page overflow in ntfs_decompress()","x_generator":{"engine":"bippy-1.2.0"}}}}