{
  "cveId": "CVE-2026-31517",
  "url": "https://patchblox.com/security/cve/CVE-2026-31517",
  "summary": "CVE-2026-31517 is fixed in linux on 1 platform by DEBIAN-CVE-2026-31517 (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:  xfrm: iptfs: fix skb_put() panic on non-linear s...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  xfrm: iptfs: fix skb_put() panic on non-linear skb during reassembly  In iptfs_reassem_cont(), IP-TFS attempts to append data to the new inner packet \u0027newskb\u0027 that is being reassembled. First a zero-copy approach is tried if it succeeds then newskb becomes non-linear.  When a subsequent fragment in the same datagram does not meet the fast-path conditions, a memory copy is performed. It calls skb_put() to append the data and as newskb is non-linear it triggers SKB_LINEAR_ASSERT check.   Oops: invalid opcode: 0000 [#1] SMP NOPTI  [...]  RIP: 0010:skb_put\u002B0x3c/0x40  [...]  Call Trace:   \u003CIRQ\u003E   iptfs_reassem_cont\u002B0x1ab/0x5e0 [xfrm_iptfs]   iptfs_input_ordered\u002B0x2af/0x380 [xfrm_iptfs]   iptfs_input\u002B0x122/0x3e0 [xfrm_iptfs]   xfrm_input\u002B0x91e/0x1a50   xfrm4_esp_rcv\u002B0x3a/0x110   ip_protocol_deliver_rcu\u002B0x1d7/0x1f0   ip_local_deliver_finish\u002B0xbe/0x1e0   __netif_receive_skb_core.constprop.0\u002B0xb56/0x1120   __netif_receive_skb_list_core\u002B0x133/0x2b0   netif_receive_skb_list_internal\u002B0x1ff/0x3f0   napi_complete_done\u002B0x81/0x220   virtnet_poll\u002B0x9d6/0x116e [virtio_net]   __napi_poll.constprop.0\u002B0x2b/0x270   net_rx_action\u002B0x162/0x360   handle_softirqs\u002B0xdc/0x510   __irq_exit_rcu\u002B0xe7/0x110   irq_exit_rcu\u002B0xe/0x20   common_interrupt\u002B0x85/0xa0   \u003C/IRQ\u003E   \u003CTASK\u003E  Fix this by checking if the skb is non-linear. If it is, linearize it by calling skb_linearize(). As the initial allocation of newskb originally reserved enough tailroom for the entire reassembled packet we do not need to check if we have enough tailroom or extend it.",
  "published": "2026-04-22T14:16:51Z",
  "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": 0.01888,
  "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-2026-31517",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-31517",
      "released": "2026-05-15T16:01:09Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T13:31:49Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}