{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-90419", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.813Z", "datePublished": "2026-09-17T16:09:43.880Z", "dateUpdated": "2026-10-19T09:03:23.291Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:03:23.291Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnilfs2: prevent out-of-bounds read in super root block parsing\n\nsuper-root inode metadata size is trusted before nilfs_read_inode_common().\n\nReject super-root inode sizes whose computed on-disk footprint exceeds the\nfilesystem block size. This prevents malformed filesystem images from\nmaking nilfs_read_inode_common() read past the end of the super-root block.\n\n[ryusuke: clarify the commit title]" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H", "baseScore": 7.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The oversized s_inode_size is on-disk in the nilfs2 superblock; nilfs_store_disk_layout() stores it and nilfs_load_super_root() indexes the super-root buffer with NILFS_SR_CPFILE_OFFSET during local mount (nilfs_get_tree → nilfs_fill_super → init_nilfs/load_nilfs). No network protocol carries s_inode_size.\nAC:L - A crafted s_inode_size that still passes ns_inode_size <= ns_blocksize but makes NILFS_SR_BYTES(inode_size) exceed ns_blocksize (for example inode_size == blocksize) puts NILFS_SR_CPFILE_OFFSET/SUFILE_OFFSET past bh_sr->b_data, so nilfs_read_inode_common() over-reads on every mount of that image. There is no race.\nPR:N - Crafting the image needs no host account. nilfs_fs_type.fs_flags is only FS_REQUIRES_DEV (no FS_USERNS_MOUNT), so mount_capable() requires init-namespace CAP_SYS_ADMIN; that privileged mount is the victim's action and is scored as UI:R, not attacker privilege.\nUI:R - The over-read runs only in nilfs_load_super_root() from nilfs_fill_super() after a victim or automounter mounts the attacker-supplied nilfs2 image via mount/fsopen. That mount is the required user interaction.\nS:U - nilfs_read_inode_common()'s over-read of the super-root buffer_head stays in the host kernel mount path and does not cross a VM, IOMMU, or sandbox authority.\nC:H - With inode_size == ns_blocksize, NILFS_SR_CPFILE_OFFSET is 16 bytes past the super-root block, and nilfs_read_inode_common() loads a full 128-byte struct nilfs_inode (including a 56-byte i_bmap memcpy in nilfs_bmap_read) from that address. That is not a few-byte leak.\nI:N - The defect is a source over-read into in-bounds VFS inode and bmap fields; there is no store through the out-of-bounds pointer and no OOB write. Leaked i_bmap words are used only as on-disk block numbers, not as a kernel write primitive.\nA:H - A 4K block with inode_size == 4096 places the cpfile inode 16 bytes past the page-backed super-root buffer, so the 128-byte load can fault on an unmapped next linear-map page (KASAN, debug_pagealloc, page poisoning) and oops the mounting kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/nilfs2/the_nilfs.c" ], "versions": [ { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "16df2520502867a4f34e202b89d01243d59bb8b5", "status": "affected", "versionType": "git" }, { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "dcc85fc28f884038735464f6f104dda9c7dbfad6", "status": "affected", "versionType": "git" }, { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "5b69ebe20d7f944c1f45177dca0c11474ac277cc", "status": "affected", "versionType": "git" }, { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "7029e70cf86d5c54c0a2812479b0bee2cabcbaaa", "status": "affected", "versionType": "git" }, { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "71bd64471ff583101b4a33dfc838ce29aef57960", "status": "affected", "versionType": "git" }, { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "842397fdfd2e61d6470166c796f3125b6c27a162", "status": "affected", "versionType": "git" }, { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "15c8559376416a84c3d8402fd8d0c89bb323d05f", "status": "affected", "versionType": "git" }, { "version": "8a9d2191e9f43bbcd256a9a6871bd73434c83f2f", "lessThan": "7cb2f76a6a2ba2130b577cb8ac13e1e46c4fc689", "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/nilfs2/the_nilfs.c" ], "versions": [ { "version": "2.6.30", "status": "affected" }, { "version": "0", "lessThan": "2.6.30", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "2.6.30", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.12.110" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.18.52" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "7.2.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/16df2520502867a4f34e202b89d01243d59bb8b5" }, { "url": "https://git.kernel.org/stable/c/dcc85fc28f884038735464f6f104dda9c7dbfad6" }, { "url": "https://git.kernel.org/stable/c/5b69ebe20d7f944c1f45177dca0c11474ac277cc" }, { "url": "https://git.kernel.org/stable/c/7029e70cf86d5c54c0a2812479b0bee2cabcbaaa" }, { "url": "https://git.kernel.org/stable/c/71bd64471ff583101b4a33dfc838ce29aef57960" }, { "url": "https://git.kernel.org/stable/c/842397fdfd2e61d6470166c796f3125b6c27a162" }, { "url": "https://git.kernel.org/stable/c/15c8559376416a84c3d8402fd8d0c89bb323d05f" }, { "url": "https://git.kernel.org/stable/c/7cb2f76a6a2ba2130b577cb8ac13e1e46c4fc689" } ], "title": "nilfs2: prevent out-of-bounds read in super root block parsing", "x_generator": { "engine": "bippy-1.2.0" } } } }