{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-68141",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2026-68141"
  ],
  "published": "2026-08-10T12:08:00Z",
  "summary": "net/af_iucv: fix NULL deref in afiucv_hs_callback_syn()",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/af_iucv: fix NULL deref in afiucv_hs_callback_syn()\n\nafiucv_hs_callback_syn() allocates the child socket with GFP_ATOMIC.\nIf the allocation fails, nsk is NULL.\n\nThe connection-refused path is entered when the listen state check\nfails, the accept backlog is full, or nsk is NULL. The code\nunconditionally calls iucv_sock_kill(nsk) in that path.\n\niucv_sock_kill() does not accept a NULL socket pointer and immediately\ndereferences sk via sock_flag(sk, SOCK_ZAPPED). When nsk is NULL,\ncalling iucv_sock_kill(nsk) results in a NULL pointer dereference.\n\nOnly call iucv_sock_kill() when a child socket was successfully\nallocated.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.183",
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-68141"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/6a1eb5b46c19073f8153b7e2c19b408cf353aaf1"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c0b6e2ae90613c2fea7eaf3faa20985c6c2a1953"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/07e21deb3664001995e0a456dd627ab7dbe127ec"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8bb111f87ded6acb9837ec9b45d6f02cda94c51f"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/46453b16f38ec7147351f7447e2aec6ea330f7b3"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/33736ff5e7c97d3348ce812e8bd2e125d840743c"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/0e857185591fe79934427c9c0c1c31dc776be134"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/47a5116e56a6b6fe1e909f244e39cd0fc26ceee4"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-19T16:47:12Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 7.5,
      "cvss_v3_severity": "High",
      "scenario": "AV:N - The flaw is reached from afiucv_hs_rcv() via dev_add_pack() when ETH_P_AF_IUCV SYN frames arrive on a HiperSockets netdev in netif RX softirq; a remote LPAR/guest on the IBM Z HiperSockets fabric can send these connection requests without local access.\nAC:L - An attacker can repeatedly send SYN packets to a listening AF_IUCV service to pressure GFP_ATOMIC socket allocations until iucv_sock_alloc() fails and the broken connection-refused path runs; no timing race or victim-specific state beyond routine memory pressure is required.\nPR:N - Exploitation requires only sending unauthenticated HiperSockets SYN traffic to a bound/listening AF_IUCV socket; the handshake path has no credential checks and the af_iucv code performs no capability or permission validation before reaching afiucv_hs_callback_syn().\nUI:N - Triggering the NULL dereference needs no action from an end user beyond a service already listening on HiperSockets; the attacker can initiate SYN packets remotely without victim interaction.\nS:U - Impact is a kernel NULL pointer dereference and likely oops/panic in the victim LPAR kernel; it does not cross a VM/host, IOMMU, or sandbox boundary to compromise a different security authority.\nC:N - The failure is an immediate NULL pointer dereference in sock_flag() inside iucv_sock_kill(); there is no memory corruption, out-of-bounds access, or use-after-free that could yield information disclosure.\nI:N - The bug does not write attacker-controlled data or corrupt kernel structures; it only dereferences a NULL socket pointer during cleanup, so no integrity impact or code-execution primitive is created.\nA:H - A NULL dereference in afiucv_hs_callback_syn() during softirq packet processing can cause a kernel oops or panic, denying all service on the affected IBM Z LPAR until reboot."
    }
  }
}