{
  "cveId": "CVE-2021-47638",
  "url": "https://patchblox.com/security/cve/CVE-2021-47638",
  "summary": "CVE-2021-47638 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47638, released February 26, 2025. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  ubifs: rename_whiteout: Fix double free for whit...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  ubifs: rename_whiteout: Fix double free for whiteout_ui-\u003Edata  \u0027whiteout_ui-\u003Edata\u0027 will be freed twice if space budget fail for rename whiteout operation as following process:  rename_whiteout   dev = kmalloc   whiteout_ui-\u003Edata = dev   kfree(whiteout_ui-\u003Edata)  // Free first time   iput(whiteout)     ubifs_free_inode       kfree(ui-\u003Edata)\t    // Double free!  KASAN reports: ================================================================== BUG: KASAN: double-free or invalid-free in ubifs_free_inode\u002B0x4f/0x70 Call Trace:   kfree\u002B0x117/0x490   ubifs_free_inode\u002B0x4f/0x70 [ubifs]   i_callback\u002B0x30/0x60   rcu_do_batch\u002B0x366/0xac0   __do_softirq\u002B0x133/0x57f  Allocated by task 1506:   kmem_cache_alloc_trace\u002B0x3c2/0x7a0   do_rename\u002B0x9b7/0x1150 [ubifs]   ubifs_rename\u002B0x106/0x1f0 [ubifs]   do_syscall_64\u002B0x35/0x80  Freed by task 1506:   kfree\u002B0x117/0x490   do_rename.cold\u002B0x53/0x8a [ubifs]   ubifs_rename\u002B0x106/0x1f0 [ubifs]   do_syscall_64\u002B0x35/0x80  The buggy address belongs to the object at ffff88810238bed8 which belongs to the cache kmalloc-8 of size 8 ==================================================================  Let ubifs_free_inode() free \u0027whiteout_ui-\u003Edata\u0027. BTW, delete unused assignment \u0027whiteout_ui-\u003Edata_len = 0\u0027, process \u0027ubifs_evict_inode() -\u003E ubifs_jnl_delete_inode() -\u003E ubifs_jnl_write_inode()\u0027 doesn\u0027t need it (because \u0027inc_nlink(whiteout)\u0027 won\u0027t be excuted by \u0027goto out_release\u0027,  and the nlink of whiteout inode is 0).",
  "published": "2025-02-26T06:37:05Z",
  "severity": "medium",
  "cvss": 5.5,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.0026,
  "epssPercentile": 0.17857,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "5.17.3-1",
      "fix": "DEBIAN-CVE-2021-47638",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47638",
      "released": "2025-02-26T06:37:05Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "5.17.3-1",
      "fix": "DEBIAN-CVE-2021-47638",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47638",
      "released": "2025-02-26T06:37:05Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "5.17.3-1",
      "fix": "DEBIAN-CVE-2021-47638",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47638",
      "released": "2025-02-26T06:37:05Z"
    }
  ],
  "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"
  }
}