{
  "cveId": "CVE-2026-92499",
  "url": "https://patchblox.com/security/cve/CVE-2026-92499",
  "summary": "CVE-2026-92499 is fixed in 20 products on 1 platform, first by DEBIAN-CVE-2026-92499, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  ext4: validate readdir offset before accessing d...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  ext4: validate readdir offset before accessing dirent  A corrupted directory can trigger the following KASAN report when ext4_readdir() resumes from an invalid position:    BUG: KASAN: use-after-free in __ext4_check_dir_entry\u002B0x5ef/0x820   Read of size 2 at addr ffff88810a646000 by task repro_linear/509    Call Trace:    \u003CTASK\u003E    dump_stack_lvl\u002B0x53/0x70    print_report\u002B0xd0/0x630    kasan_report\u002B0xce/0x100    __ext4_check_dir_entry\u002B0x5ef/0x820    ext4_readdir\u002B0xcde/0x2b70    iterate_dir\u002B0x1a1/0x520    __x64_sys_getdents64\u002B0x12b/0x220    do_syscall_64\u002B0xf9/0x540    entry_SYSCALL_64_after_hwframe\u002B0x77/0x7f    \u003C/TASK\u003E  KASAN reports use-after-free because the out-of-bounds access lands in an adjacent freed page. The directory buffer itself is still referenced.  ext4_dir_llseek() invalidates the directory cookie so that ext4_readdir() rescans directory entries from the start of the block. The rescan checks only the lower bound of rec_len before advancing. A corrupted rec_len can therefore place the offset where the block has insufficient space for a complete directory entry. The rescan itself may dereference that truncated entry, or the main loop may pass it to __ext4_check_dir_entry(). The latter reads de-\u003Erec_len before validating the range. For example:    block offset  0                           4092  4096                 |---- de1.rec_len = 4092 -----|----|                                                de2.inode                                                     | de2.rec_len                                                     ^ OOB, reported as UAF  de2 starts at offset 4092 in this 4 KiB block. Its four-byte inode fits in the block, but its rec_len starts at offset 4096 and crosses the boundary.  The minimum safe length is inode-dependent. Encrypted and casefolded directory entries need eight additional hash bytes, while a valid metadata checksum tail is only 12 bytes.  Cache the metadata checksum feature state and derive the minimum directory entry length from the on-disk format. Use it to bound both the rescan and the offset passed to the main loop. Report an offset in a truncated block tail and skip the remainder of the block, while continuing to accept an offset exactly at the block boundary.",
  "published": "2026-09-17T17:17:52Z",
  "severity": "important",
  "epss": 0.00198,
  "epssPercentile": 0.09626,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "bpftool6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "bpftool6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel-livepatch-6.18.54-121.166",
      "release": "amzn 2023",
      "fixedVersion": "1:1.0-0.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-aarch64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-x86_64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-headers",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra-common",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-92499",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-92499",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "microvm-kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
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      "product": "perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.54-121.166.amzn2023",
      "fix": "ALAS2023-2026-3192",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3192",
      "released": "2026-11-07T01:06:07Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T01:18:40Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}