{
  "cveId": "CVE-2026-74343",
  "url": "https://patchblox.com/security/cve/CVE-2026-74343",
  "summary": "CVE-2026-74343 is fixed in linux on 1 platform by DEBIAN-CVE-2026-74343 (version 7.1.5-1), released August 15, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  kernfs: fix xattr race condition with multiple s...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  kernfs: fix xattr race condition with multiple superblocks  Multiple superblocks with different namespaces can share the same kernfs_node when kernfs_test_super() finds a matching root but different namespace. This means multiple inodes from different superblocks can reference the same kernfs_node-\u003Eiattr-\u003Exattrs structure.  The VFS layer only holds per-inode locks during xattr operations, which is insufficient to serialize concurrent xattr modifications on the shared kernfs_node. This can lead to race conditions in simple_xattr_set() where the lookup-\u003Ereplace/remove sequence is not atomic with respect to operations from other superblocks.  Fix this by protecting xattr operations with the existing hashed kernfs_locks-\u003Eopen_file_mutex[] array, which is already used to protect per-node open file data. The hashed mutex array provides scalable per-node serialization (scaled by CPU count, up to 1024 locks on 32\u002B CPU systems) with zero memory overhead.  Changes: - Rename open_file_mutex[] to node_mutex[] to reflect dual purpose - Add kernfs_node_lock_ptr() and kernfs_node_lock() helpers - Protect simple_xattr_set() calls in kernfs_xattr_set() and   kernfs_vfs_user_xattr_set() with the hashed mutex - Update file.c to use new helpers via compatibility wrappers - Update documentation to explain the extended lock usage",
  "published": "2026-08-15T06:22:35Z",
  "severity": "high",
  "cvss": 7.8,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00165,
  "epssPercentile": 0.0576,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.1.5-1",
      "fix": "DEBIAN-CVE-2026-74343",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-74343",
      "released": "2026-08-15T22:38:55Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}