{"id":"CVE-2026-92499","aliases":[],"cve":{"records":[{"id":"CVE-2026-92499","source":"Linux","state":"PUBLISHED","reasons":[],"replacements":[],"disputed":false,"unsupportedWhenAssigned":false,"reserved":"2026-09-16T12:21:13.871Z","published":"2026-09-17T16:10:13.391Z","modified":"2026-11-10T18:15:10.609Z"}],"publishers":[{"name":"Linux","role":"CNA","organizationId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","modified":"2026-11-10T18:15:10.609Z"}],"references":[{"url":"https://git.kernel.org/stable/c/094e8139cf5a5e37b363ac984f628359558415e6","tags":[],"source":"Linux"},{"url":"https://git.kernel.org/stable/c/64d445d40e5ea4c4d4d88880db753b370cb69161","tags":[],"source":"Linux"},{"url":"https://git.kernel.org/stable/c/b4c728577933753180e3e97f08424d5bcaff705e","tags":[],"source":"Linux"},{"url":"https://git.kernel.org/stable/c/bc4b7b0414c33b2c8898eb04386df0d21a13dad8","tags":[],"source":"Linux"}],"weaknesses":[],"applicability":[{"source":"Linux","statements":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"6.12.117"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.19","versionEndExcluding":"7.3"}]}]}]}],"prioritization":[]},"title":"ext4: validate readdir offset before accessing dirent","titleSource":"Linux","descriptionSource":"Linux","description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: validate readdir offset before accessing dirent\n\nA corrupted directory can trigger the following KASAN report when\next4_readdir() resumes from an invalid position:\n\n  BUG: KASAN: use-after-free in __ext4_check_dir_entry+0x5ef/0x820\n  Read of size 2 at addr ffff88810a646000 by task repro_linear/509\n\n  Call Trace:\n   <TASK>\n   dump_stack_lvl+0x53/0x70\n   print_report+0xd0/0x630\n   kasan_report+0xce/0x100\n   __ext4_check_dir_entry+0x5ef/0x820\n   ext4_readdir+0xcde/0x2b70\n   iterate_dir+0x1a1/0x520\n   __x64_sys_getdents64+0x12b/0x220\n   do_syscall_64+0xf9/0x540\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n   </TASK>\n\nKASAN reports use-after-free because the out-of-bounds access lands in an\nadjacent freed page. The directory buffer itself is still referenced.\n\next4_dir_llseek() invalidates the directory cookie so that ext4_readdir()\nrescans directory entries from the start of the block. The rescan checks\nonly the lower bound of rec_len before advancing. A corrupted rec_len can\ntherefore place the offset where the block has insufficient space for a\ncomplete directory entry. The rescan itself may dereference that truncated\nentry, or the main loop may pass it to __ext4_check_dir_entry(). The latter\nreads de->rec_len before validating the range. For example:\n\n  block offset  0                           4092  4096\n                |---- de1.rec_len = 4092 -----|----|\n                                               de2.inode\n                                                    | de2.rec_len\n                                                    ^ OOB, reported as UAF\n\nde2 starts at offset 4092 in this 4 KiB block. Its four-byte inode fits in\nthe block, but its rec_len starts at offset 4096 and crosses the boundary.\n\nThe minimum safe length is inode-dependent. Encrypted and casefolded\ndirectory entries need eight additional hash bytes, while a valid metadata\nchecksum tail is only 12 bytes.\n\nCache the metadata checksum feature state and derive the minimum directory\nentry length from the on-disk format. Use it to bound both the rescan and\nthe offset passed to the main loop. Report an offset in a truncated block\ntail and skip the remainder of the block, while continuing to accept an\noffset exactly at the block boundary.","score":null,"severity":"unknown","published":"2026-09-17T16:10:13.391Z","modified":"2026-11-10T18:15:10.609Z","withdrawn":false,"knownExploited":false,"affected":[],"products":[{"vendor":"Linux","name":"Linux","platforms":[],"versions":[{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","status":"affected","lessThan":"094e8139cf5a5e37b363ac984f628359558415e6","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","status":"affected","lessThan":"64d445d40e5ea4c4d4d88880db753b370cb69161","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","status":"affected","lessThan":"b4c728577933753180e3e97f08424d5bcaff705e","versionType":"git"},{"version":"ac27a0ec112a089f1a5102bc8dffc79c8c815571","status":"affected","lessThan":"bc4b7b0414c33b2c8898eb04386df0d21a13dad8","versionType":"git"}],"defaultStatus":"unaffected","cpes":[],"source":"Linux","url":"https://www.cve.org/CVERecord?id=CVE-2026-92499"},{"vendor":"Linux","name":"Linux","platforms":[],"versions":[{"version":"2.6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.19","versionType":"semver"},{"version":"6.12.117","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"defaultStatus":"affected","cpes":[],"source":"Linux","url":"https://www.cve.org/CVERecord?id=CVE-2026-92499"}],"remediation":[],"references":["https://git.kernel.org/stable/c/094e8139cf5a5e37b363ac984f628359558415e6","https://git.kernel.org/stable/c/64d445d40e5ea4c4d4d88880db753b370cb69161","https://git.kernel.org/stable/c/b4c728577933753180e3e97f08424d5bcaff705e","https://git.kernel.org/stable/c/bc4b7b0414c33b2c8898eb04386df0d21a13dad8"],"sources":[{"name":"CVE","id":"CVE-2026-92499","modified":"2026-11-10T18:15:10.609Z","url":"https://www.cve.org/CVERecord?id=CVE-2026-92499"}],"assessments":[],"sourceAffected":[],"observedAt":"2026-11-10T18:24:53.690Z","kev":{"status":"not-listed","checkedAt":"2026-11-15T02:25:31.038Z"},"coverage":[{"source":"NVD","status":"not-checked"},{"source":"GHSA","status":"available","checkedAt":"2026-11-15T02:10:35.821Z","attemptedAt":"2026-11-15T02:10:35.821Z"},{"source":"EUVD","status":"available","checkedAt":"2026-11-15T02:10:35.707Z","attemptedAt":"2026-11-15T02:10:35.707Z"},{"source":"EPSS","status":"available","checkedAt":"2026-11-15T02:10:30.935Z","attemptedAt":"2026-11-15T02:10:30.935Z"}],"evidence":[{"source":"FIRST EPSS","id":"CVE-2026-92499","url":"https://www.first.org/epss/","probability":0.002,"percentile":0.09954,"date":"2026-11-14","checkedAt":"2026-11-15T02:10:30.935Z"},{"source":"ENISA EUVD","id":"EUVD-2026-82120","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-82120","modified":"Nov 10, 2026, 6:15:10 PM","checkedAt":"2026-11-15T02:10:35.707Z"},{"source":"GitHub Advisory Database","id":"GHSA-5fwr-5mg2-3p42","url":"https://github.com/advisories/GHSA-5fwr-5mg2-3p42","modified":"2026-11-10T21:32:40Z","checkedAt":"2026-11-15T02:10:35.821Z"}],"aiSummary":{"text":"The Linux kernel's ext4 file system is vulnerable to a use-after-free error when accessing a corrupted directory, potentially causing a crash. The issue affects Linux kernel versions starting from 2.6.19 up to but not including 6.12.117, 6.18.52, and 7.2.6. An attacker with access to the system would need to create a corrupted directory to exploit this vulnerability.","model":"@cf/meta/llama-3.3-70b-instruct-fp8-fast","generatedAt":"2026-11-10T18:41:17.511Z","sources":[{"name":"CVE","url":"https://www.cve.org/CVERecord?id=CVE-2026-92499"}]}}