{
  "cveId": "CVE-2026-23143",
  "url": "https://patchblox.com/security/cve/CVE-2026-23143",
  "summary": "CVE-2026-23143 is fixed in linux on 1 platform, first by DEBIAN-CVE-2026-23143, released February 14, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  virtio_net: Fix misalignment bug in struct virtn...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  virtio_net: Fix misalignment bug in struct virtnet_info  Use the new TRAILING_OVERLAP() helper to fix a misalignment bug along with the following warning:  drivers/net/virtio_net.c:429:46: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]  This helper creates a union between a flexible-array member (FAM) and a set of members that would otherwise follow it (in this case \u0060u8 rss_hash_key_data[VIRTIO_NET_RSS_MAX_KEY_SIZE];\u0060). This overlays the trailing members (rss_hash_key_data) onto the FAM (hash_key_data) while keeping the FAM and the start of MEMBERS aligned. The static_assert() ensures this alignment remains.  Notice that due to tail padding in flexible \u0060struct virtio_net_rss_config_trailer\u0060, \u0060rss_trailer.hash_key_data\u0060 (at offset 83 in struct virtnet_info) and \u0060rss_hash_key_data\u0060 (at offset 84 in struct virtnet_info) are misaligned by one byte. See below:  struct virtio_net_rss_config_trailer {         __le16                     max_tx_vq;            /*     0     2 */         __u8                       hash_key_length;      /*     2     1 */         __u8                       hash_key_data[];      /*     3     0 */          /* size: 4, cachelines: 1, members: 3 */         /* padding: 1 */         /* last cacheline: 4 bytes */ };  struct virtnet_info { ...         struct virtio_net_rss_config_trailer rss_trailer; /*    80     4 */          /* XXX last struct has 1 byte of padding */          u8                         rss_hash_key_data[40]; /*    84    40 */ ...         /* size: 832, cachelines: 13, members: 48 */         /* sum members: 801, holes: 8, sum holes: 31 */         /* paddings: 2, sum paddings: 5 */ };  After changes, those members are correctly aligned at offset 795:  struct virtnet_info { ...         union {                 struct virtio_net_rss_config_trailer rss_trailer; /*   792     4 */                 struct {                         unsigned char __offset_to_hash_key_data[3]; /*   792     3 */                         u8         rss_hash_key_data[40]; /*   795    40 */                 };                                       /*   792    43 */         };                                               /*   792    44 */ ...         /* size: 840, cachelines: 14, members: 47 */         /* sum members: 801, holes: 8, sum holes: 35 */         /* padding: 4 */         /* paddings: 1, sum paddings: 4 */         /* last cacheline: 8 bytes */ };  As a result, the RSS key passed to the device is shifted by 1 byte: the last byte is cut off, and instead a (possibly uninitialized) byte is added at the beginning.  As a last note \u0060struct virtio_net_rss_config_hdr *rss_hdr;\u0060 is also moved to the end, since it seems those three members should stick around together. :)",
  "published": "2026-02-14T16:15:54Z",
  "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": 0.00174,
  "epssPercentile": 0.069,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.115-2",
      "fix": "DEBIAN-CVE-2026-23143",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-23143",
      "released": "2026-02-14T16:15:54Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "6.18.8-1",
      "fix": "DEBIAN-CVE-2026-23143",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-23143",
      "released": "2026-02-14T16:15:54Z"
    }
  ],
  "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"
  }
}