{
  "cveId": "CVE-2026-31437",
  "url": "https://patchblox.com/security/cve/CVE-2026-31437",
  "summary": "CVE-2026-31437 is fixed in linux on 1 platform by DEBIAN-CVE-2026-31437 (version 6.19.11-1), released May 15, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  netfs: Fix NULL pointer dereference in netfs_unb...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  netfs: Fix NULL pointer dereference in netfs_unbuffered_write() on retry  When a write subrequest is marked NETFS_SREQ_NEED_RETRY, the retry path in netfs_unbuffered_write() unconditionally calls stream-\u003Eprepare_write() without checking if it is NULL.  Filesystems such as 9P do not set the prepare_write operation, so stream-\u003Eprepare_write remains NULL. When get_user_pages() fails with -EFAULT and the subrequest is flagged for retry, this results in a NULL pointer dereference at fs/netfs/direct_write.c:189.  Fix this by mirroring the pattern already used in write_retry.c: if stream-\u003Eprepare_write is NULL, skip renegotiation and directly reissue the subrequest via netfs_reissue_write(), which handles iterator reset, IN_PROGRESS flag, stats update and reissue internally.",
  "published": "2026-04-22T14:16:36Z",
  "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": 0.00121,
  "epssPercentile": 0.01906,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "6.19.11-1",
      "fix": "DEBIAN-CVE-2026-31437",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-31437",
      "released": "2026-05-15T16:01:09Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}