{"cve":"CVE-2026-90133","nvd":{"published":"2026-09-17T17:17:05.837","modified":"2026-10-19T09:19:03.063","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: Fix index_root heap OOB write in ntfs_ir_to_ib()\n\nntfs_ir_to_ib copies all entries from index_root into a freshly allocated\nindex_block_size-byte buffer without verifying that the entries fit in the\navailable space. The entries in index_root may be larger than the usable\nentry space in the index block.\n\nThis can cause OOB writes past the end of the allocation.\n\nThe validator ntfs_index_root_inconsistent() checks that entries are\nself-consistent within the IR value, but never cross-checks them against\nindex_block_size. There is no bounds check in ntfs_ir_to_ib() before the\nmemcpy.\n\nFixing this at the sink in ntfs_ir_to_ib() since\nntfs_index_root_inconsistent() validates the logical consistency of\nindex_root as a structure and a root with large entries is a structurally\nvalid root. The bug is a size conflict of ntfs_ir_to_ib().\nAlso, the validator is called once per inode load in\nntfs_read_locked_inode() while ntfs_ir_to_ib() is only called during a\nreparent, a check there adds no overhead to the common path.\nMoreover, even a future call path that bypasses the validator would still\nbe protected.\n\nWith NULL as first parameter of ntfs_error(), the volume error flag is\nnever set by this call, so the device name will be absent from the error\nmessage. In any case, that the caller, ntfs_ir_reparent(), prints an error\nmessage that includes the device name on NULL returns.\nI think this is the best solution available without adding\n'struct super_block *sb' as a parameter to ntfs_ir_to_ib().\n\nThis heap out-of-bounds write is triggered by a crafted filesystem image,\nwhich is not in the kernel threat model, anyway, fixing memory errors would\nbe nice to keep  things secure.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/825dec5120933e90c54e30e31ccfa6c3449043a8","https://git.kernel.org/stable/c/dc09bf79b76f9a7157e225f449655f3f62f96c9c"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-90133","score":0.00205,"percentile":0.10321,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}