{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.180-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.100-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.1.5-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  vhost/net: complete zerocopy ubufs only once  vhost-net initializes one ubuf_info per outstanding zerocopy TX descriptor and hands it to the backend socket.  The networking stack may then clone a zerocopy skb before all skb references are released.  For example, batman-adv fragmentation reaches skb_split(), which calls skb_zerocopy_clone() and increments the same ubuf_info refcount.  vhost_zerocopy_complete() currently treats every ubuf callback as a completed vhost descriptor.  It dereferences ubuf-\u003ectx, writes the descriptor completion state, and drops the vhost_net_ubuf_ref even when the callback only releases a cloned skb reference.  A backend reset can therefore wait for and free the vhost_net_ubuf_ref while another cloned skb still carries the same ubuf_info.  A later completion then dereferences the freed ubufs pointer.  KASAN reports the stale completion as:    BUG: KASAN: slab-use-after-free in vhost_zerocopy_complete+0x1d7/0x1f0   BUG: KASAN: slab-use-after-free in vhost_zerocopy_complete+0x101/0x1f0   vhost_zerocopy_complete   skb_copy_ubufs   __dev_forward_skb2   veth_xmit  The freed object was allocated from vhost_net_ioctl() while setting the backend and freed through kfree_rcu()/kvfree_rcu_bulk after backend removal, while delayed skb completion still reached vhost_zerocopy_complete().  Honor the generic ubuf_info refcount before touching vhost state, and run the vhost descriptor completion only for the final ubuf reference.  This matches the msg_zerocopy_complete() ownership rule for cloned zerocopy skbs.",
  "id": "DEBIAN-CVE-2026-74310",
  "modified": "2026-09-14T16:47:46.824519239Z",
  "published": "2026-08-15T06:22:30.987Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-74310"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-74310"
  ]
}