{"id":"CVE-2026-89786","title":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix out-of-bounds read in ext4_read_inline_dir()\n\next4_read_inline_dir() can read a dirent header past the end of its inline\nbuffer, triggering a slab-out-of-boun…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix out-of-bounds read in ext4_read_inline_dir()\n\next4_read_inline_dir() can read a dirent header past the end of its inline\nbuffer, triggering a slab-out-of-boun…","severity":"critical","cvss":9.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","vendor":"Linux","product":"Linux","affected":["Linux >= c4d8b0235aa98f8c26bf94d308be3fdd24154572 < d1e7c186555ad65554fd2f2b02f5a539aa35ae48","Linux >= c4d8b0235aa98f8c26bf94d308be3fdd24154572 < 5fd20d4e50dd6e460b3ea8e4396f8553d4526f8f","Linux >= c4d8b0235aa98f8c26bf94d308be3fdd24154572 < 1a1dea633b724a1c042dbcdb1fed27f410916688","Linux >= c4d8b0235aa98f8c26bf94d308be3fdd24154572 < b060861f662d4826dc700a1c3584243bb3474cfe","Linux >= c4d8b0235aa98f8c26bf94d308be3fdd24154572 < 6702c7da86d8cdb88d0fc57166286e115ffeb8c0","Linux >= c4d8b0235aa98f8c26bf94d308be3fdd24154572 < 36bf17bb90cdf7a623499b624b05acde4d2feef5","Linux >= c4d8b0235aa98f8c26bf94d308be3fdd24154572 < 9333cc809f0a89e001b814155a6cb8903a6274df","Linux 3.10"],"published":"2026-09-16","updated":"2026-09-16","sourceUpdated":"2026-09-16T15:18:08.860","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-89786","references":[{"url":"https://git.kernel.org/stable/c/1a1dea633b724a1c042dbcdb1fed27f410916688","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/36bf17bb90cdf7a623499b624b05acde4d2feef5","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5fd20d4e50dd6e460b3ea8e4396f8553d4526f8f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6702c7da86d8cdb88d0fc57166286e115ffeb8c0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9333cc809f0a89e001b814155a6cb8903a6274df","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b060861f662d4826dc700a1c3584243bb3474cfe","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d1e7c186555ad65554fd2f2b02f5a539aa35ae48","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-16T08:52:29.590Z","epss":0.00688,"epssPercentile":0.50872,"slug":"CVE-2026-89786","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\next4: fix out-of-bounds read in ext4_read_inline_dir()\n\next4_read_inline_dir() can read a dirent header past the end of its inline\nbuffer, triggering a slab-out-of-bounds read during getdents64():\n\n  BUG: KASAN: slab-out-of-bounds in __ext4_check_dir_entry\n  Read of size 2 at addr ffff88800f3dd23c by task exploit/148\n   ...\n   __ext4_check_dir_entry\n   ext4_read_inline_dir\n   iterate_dir\n\nThe dirent payload lives in a buffer of exactly inline_size bytes:\n\n\tdir_buf = kmalloc(inline_size, GFP_NOFS);\n\nbut iteration runs in a position space extra_offset bytes larger\n(extra_size = extra_offset + inline_size) so the synthetic \".\" and \"..\"\nland at their block-dir offsets. A dirent is formed at \"dir_buf + pos -\nextra_offset\", yet the ext4_check_dir_entry() length argument uses the\nlarger extra_size. A position whose dirent header would extend past\nextra_size is therefore accepted, and the rescan loop's rec_len probe and\next4_check_dir_entry() dereference de->rec_len before the entry is rejected.\n\nReject a position whose minimum-size dirent header would not fit within\nextra_size before forming de, in both the rescan and main loops, and pass\ninline_size rather than extra_size to ext4_check_dir_entry() so the length\ncheck matches the physical buffer.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":50,"depthScoreParts":{"impact":50.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":205263,"id":"CVE-2026-89786","ts":1789570705998,"field":"cvss","old":null,"new":"9.1"},{"seq":205262,"id":"CVE-2026-89786","ts":1789570705998,"field":"severity","old":"none","new":"critical"}]}