{"schema_version":"1.7.5","id":"CVE-2026-63818","published":"2026-07-19T12:02:17.022Z","modified":"2026-07-25T04:14:49.254293833Z","related":["openSUSE-SU-2026:11339-1"],"summary":"f2fs: validate orphan inode entry count","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: validate orphan inode entry count\n\nf2fs_recover_orphan_inodes() trusts the orphan block entry_count when\nreplaying orphan inodes from the checkpoint pack. A corrupted entry_count\nlarger than F2FS_ORPHANS_PER_BLOCK makes the recovery loop read past the\nino[] array and interpret footer or following data as inode numbers.\n\nOn a crafted image, mounting an unpatched kernel can drive orphan recovery\ninto f2fs_bug_on() and panic the kernel. Validate entry_count before\nconsuming entries so corrupted checkpoint data fails the mount with\n-EFSCORRUPTED and requests fsck instead.\n\nSet ERROR_INCONSISTENT_ORPHAN as well, so the corruption reason can be\nrecorded in the superblock s_errors[] field. This gives fsck a persistent\nhint even though mount-time orphan recovery failure may leave no chance to\npersist SBI_NEED_FSCK through a checkpoint.","affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"127e670abfa7fa150f6550d620ded930f5bdb4e7"},{"fixed":"210c210c92d78fdf5051bc55c5c69044b1a2150a"},{"fixed":"ad101d15716f5a24d1fa82a849f80430c805a3dd"},{"fixed":"d18c81f5d0ecd5796aa47d66d98f2dd54d8d0f70"},{"fixed":"d2f236196d542ccd8505736e41c3a1d3f0305f6f"},{"fixed":"550511a2470f6d204fa07b331f048bd2d3c51280"},{"fixed":"8aad54746c251f2c2370118df766c0c82e2d2091"},{"fixed":"2e12381d4495dc8b0ff042c6856022b2e359835c"},{"fixed":"846c499a65816d13f1186e3090e825e8bb8bcb8b"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63818.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.8.0"},{"fixed":"5.10.261"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.38"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63818.json"}}],"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/210c210c92d78fdf5051bc55c5c69044b1a2150a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2e12381d4495dc8b0ff042c6856022b2e359835c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/550511a2470f6d204fa07b331f048bd2d3c51280"},{"type":"WEB","url":"https://git.kernel.org/stable/c/846c499a65816d13f1186e3090e825e8bb8bcb8b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8aad54746c251f2c2370118df766c0c82e2d2091"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ad101d15716f5a24d1fa82a849f80430c805a3dd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d18c81f5d0ecd5796aa47d66d98f2dd54d8d0f70"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d2f236196d542ccd8505736e41c3a1d3f0305f6f"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63818.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63818"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63818.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}