{"id":"CVE-2026-72225","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-72225","summary":"jbd2: fix integer underflow in jbd2_journal_initialize_fast_commit()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\njbd2: fix integer underflow in jbd2_journal_initialize_fast_commit()\n\njbd2_journal_initialize_fast_commit() validates journal capacity by\nchecking (journal->j_last - num_fc_blks < JBD2_MIN_JOURNAL_BLOCKS).\nBoth j_last and num_fc_blks are unsigned, so when num_fc_blks exceeds\nj_last the subtraction wraps to a large value, bypassing the bounds\ncheck.\n\nThe resulting underflow corrupts j_last, j_fc_first, and j_free,\nleading to journal abort.\n\nFix by checking num_fc_blks against j_last before the subtraction,\nreturning -EFSCORRUPTED.","published":"2026-08-15T05:54:17.541Z","modified":"2026-08-16T03:48:37.420850962Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"5.15.212"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/289a2ca0c9b7eae74f93fc213b0b971669b8683d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4450dcaadf7d4aae8b6e4223b5d6ee4eb77097a9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4b48dcb88bb9117e3d3f051175a9a8b7cff7f8b6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/78955fdce8ff654e6d33a2fa90882a1e7eb26330"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a58fc10adf503969fec2007b5afe8987258046c4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e144ad0250f77e23e28949587b8b57e40dc3b512"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fb9b49618ed7296ebfad62a3835da8945f727001"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72225.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72225"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-16T03:48:37.420850962Z"}}