{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2023-52479",
  "modified": "2026-10-09T11:39:44Z",
  "upstream": [
    "CVE-2023-52479"
  ],
  "published": "2024-02-29T05:43:35Z",
  "summary": "ksmbd: fix uaf in smb20_oplock_break_ack",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix uaf in smb20_oplock_break_ack\n\ndrop reference after use opinfo.",
  "severity": [
    {
      "type": "CVSS_V3",
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
    }
  ],
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt2",
        "1:6.1.47-1+rpt4",
        "1:6.1.54-1+rpt2"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi2-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt2"
          },
          {
            "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"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi4-rpi-2712",
            "binary_version": "1:6.1.54-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi4-rpi-v6",
            "binary_version": "1:6.1.54-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi4-rpi-v7",
            "binary_version": "1:6.1.54-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi4-rpi-v7l",
            "binary_version": "1:6.1.54-1+rpt2"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi4-rpi-v8",
            "binary_version": "1:6.1.54-1+rpt2"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt2": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.57"
          },
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.57",
            "compiled_filter": false
          },
          "1:6.1.54-1+rpt2": {
            "linux_commit": "2906f7abdc03d4a92b6b0e2e0c87ea2a9dffe8f7",
            "upstream_version": "6.1.54",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.1.57"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-52479"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/694e13732e830cbbfedb562e57f28644927c33fd"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/8226ffc759ea59f10067b9acdf7f94bae1c69930"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d5b0e9d3563e7e314a850e81f42b2ef6f39882f9"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c69813471a1ec081a0b9bf0c6bd7e8afd818afce"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-08-15T12:24:41Z",
    "severity": {
      "source": "kernel CNA",
      "cvss_v3_score": 8.8,
      "cvss_v3_severity": "High",
      "scenario": "AV:N - The vulnerable code is ksmbd's SMB2_OPLOCK_BREAK handler in fs/smb/server/smb2pdu.c, reached from SMB2 PDUs on the in-kernel SMB server listening on TCP/445; no local access is required.\nAC:L - The attacker fully controls the sequence\u2014open with an exclusive/batch oplock, trigger the break from a second connection or create, then send the oplock break ack\u2014and the success path always drops the opinfo reference before writing op_state and waking oplock_q.\nPR:L - smb2_check_user_session() rejects SMB2_OPLOCK_BREAK without a valid session, and the path also needs a tree connect plus an open handle holding an oplock, so a basic authenticated share user (or guest where permitted) is required.\nUI:N - The attacker performs every step\u2014file open, conflicting open to force the break, and the oplock break ack\u2014with no action by any legitimate user or administrator.\nS:U - The corruption and impact stay within the kernel/ksmbd security authority; this is standard kernel memory corruption, not a VM, IOMMU, or sandbox boundary escape.\nC:H - Use-after-free of struct oplock_info (and related fd/refcount state) lets an attacker reclaim and read the freed heap object via subsequent opinfo/conn/sess/o_fp dereferences, enabling arbitrary kernel memory disclosure.\nI:H - The freed oplock_info still participates in wait queues and list links; reclaiming it lets wake_up_interruptible_all() invoke attacker-controlled wait_queue_entry callbacks and list operations act as write primitives for code execution.\nA:H - Even without full exploitation, the use-after-free and possible double put on the pin-failure path reliably cause kernel oops/panic, and the attacker can repeat the sequence to keep the server unavailable."
    }
  }
}