{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-98773",
  "modified": "2026-10-19T04:30:01Z",
  "upstream": [
    "CVE-2026-98773"
  ],
  "published": "2026-10-18T15:54:51Z",
  "summary": "USB: cdc-acm: skip URB restart in port_shutdown if disconnected",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: cdc-acm: skip URB restart in port_shutdown if disconnected\n\nacm_port_shutdown() is called from the tty-port machinery whenever the\nlast user closes the port.  acm_disconnect() sets acm->disconnected and\ncalls tty_port_tty_vhangup(), which eventually triggers port_shutdown().\nAt that point acm_disconnect() has already called acm_poison_urbs() and\nis about to free the control and read URBs.\n\nHowever, acm_port_shutdown() unconditionally calls acm_unpoison_urbs()\nand, when the ALWAYS_POLL_CTRL quirk is set, immediately re-submits the\nctrlurb and all read URBs.  If the concurrent acm_disconnect() then\nfrees those URBs and their DMA buffers while they are in-flight, the\nresult is a use-after-free in acm_ctrl_irq() or acm_read_bulk_callback()\naccessing the freed DMA memory.\n\nFix by checking acm->disconnected after draining the delayed anchor and\nreturning early: if we are in a disconnect path the URBs must remain\npoisoned and must not be resubmitted.\n\nThe early return is placed after the delayed-anchor drain loop because\nthat loop only cancels write-side accounting (wb->use = false and\nautopm counter) and does not touch the hardware path.",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.12.87-1+rpt1~bookworm",
        "1:6.12.93-1+rpt1",
        "1:6.12.96-1+rpt1",
        "1:6.12.109-1+rpt1"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.12.87+rpt-rpi-2712",
            "binary_version": "1:6.12.87-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.87+rpt-rpi-v6",
            "binary_version": "1:6.12.87-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.87+rpt-rpi-v7",
            "binary_version": "1:6.12.87-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.87+rpt-rpi-v7l",
            "binary_version": "1:6.12.87-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.87+rpt-rpi-v8",
            "binary_version": "1:6.12.87-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.87+rpt-rpi-v8-rt",
            "binary_version": "1:6.12.87-1+rpt1~bookworm"
          },
          {
            "binary_name": "linux-image-6.12.93+rpt-rpi-2712",
            "binary_version": "1:6.12.93-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.93+rpt-rpi-v6",
            "binary_version": "1:6.12.93-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.93+rpt-rpi-v7",
            "binary_version": "1:6.12.93-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.93+rpt-rpi-v7l",
            "binary_version": "1:6.12.93-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.93+rpt-rpi-v8",
            "binary_version": "1:6.12.93-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.93+rpt-rpi-v8-rt",
            "binary_version": "1:6.12.93-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.96+rpt-rpi-2712",
            "binary_version": "1:6.12.96-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.96+rpt-rpi-v6",
            "binary_version": "1:6.12.96-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.96+rpt-rpi-v7",
            "binary_version": "1:6.12.96-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.96+rpt-rpi-v7l",
            "binary_version": "1:6.12.96-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.96+rpt-rpi-v8",
            "binary_version": "1:6.12.96-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.96+rpt-rpi-v8-rt",
            "binary_version": "1:6.12.96-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.109+rpt-rpi-2712",
            "binary_version": "1:6.12.109-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.109+rpt-rpi-v6",
            "binary_version": "1:6.12.109-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.109+rpt-rpi-v7",
            "binary_version": "1:6.12.109-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.109+rpt-rpi-v7l",
            "binary_version": "1:6.12.109-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.109+rpt-rpi-v8",
            "binary_version": "1:6.12.109-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.12.109+rpt-rpi-v8-rt",
            "binary_version": "1:6.12.109-1+rpt1"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.12.87-1+rpt1~bookworm": {
            "linux_commit": "ae4d75fb36deba0fe1a986d9bfae65755e082dd0",
            "upstream_version": "6.12.87",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.113"
          },
          "1:6.12.93-1+rpt1": {
            "linux_commit": "d8ab4e908235da7727f22dd36ad5af224671677d",
            "upstream_version": "6.12.93",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.113"
          },
          "1:6.12.96-1+rpt1": {
            "linux_commit": "ae161617d7a4552fa91d03626b8d9f3696d17481",
            "upstream_version": "6.12.96",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.113"
          },
          "1:6.12.109-1+rpt1": {
            "linux_commit": "7d1826930811232688a50c99c540fbb137aed081",
            "upstream_version": "6.12.109",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.12.113"
          }
        }
      }
    },
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:13",
        "name": "linux"
      },
      "versions": [
        "1:6.18.29-1+rpt1",
        "1:6.18.33-1+rpt1",
        "1:6.18.34-1+rpt1",
        "1:6.18.39-1+rpt1",
        "1:6.18.50-1+rpt1"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-2712",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v6",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v7",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v8",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.29+rpt-rpi-v8-rt",
            "binary_version": "1:6.18.29-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.33+rpt-rpi-2712",
            "binary_version": "1:6.18.33-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.33+rpt-rpi-v6",
            "binary_version": "1:6.18.33-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.33+rpt-rpi-v7",
            "binary_version": "1:6.18.33-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.33+rpt-rpi-v8",
            "binary_version": "1:6.18.33-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.33+rpt-rpi-v8-rt",
            "binary_version": "1:6.18.33-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.34+rpt-rpi-2712",
            "binary_version": "1:6.18.34-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.34+rpt-rpi-v6",
            "binary_version": "1:6.18.34-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.34+rpt-rpi-v7",
            "binary_version": "1:6.18.34-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.34+rpt-rpi-v8",
            "binary_version": "1:6.18.34-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.34+rpt-rpi-v8-rt",
            "binary_version": "1:6.18.34-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.39+rpt-rpi-2712",
            "binary_version": "1:6.18.39-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.39+rpt-rpi-v6",
            "binary_version": "1:6.18.39-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.39+rpt-rpi-v7",
            "binary_version": "1:6.18.39-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.39+rpt-rpi-v8",
            "binary_version": "1:6.18.39-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.39+rpt-rpi-v8-rt",
            "binary_version": "1:6.18.39-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.50+rpt-rpi-2712",
            "binary_version": "1:6.18.50-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.50+rpt-rpi-v6",
            "binary_version": "1:6.18.50-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.50+rpt-rpi-v7",
            "binary_version": "1:6.18.50-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.50+rpt-rpi-v8",
            "binary_version": "1:6.18.50-1+rpt1"
          },
          {
            "binary_name": "linux-image-6.18.50+rpt-rpi-v8-rt",
            "binary_version": "1:6.18.50-1+rpt1"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.18.29-1+rpt1": {
            "linux_commit": "66318c5b5cd8145a662303af12ed39ac07eb27cc",
            "upstream_version": "6.18.29",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.18.56"
          },
          "1:6.18.33-1+rpt1": {
            "linux_commit": "95b85bebbedcaedfa7ca79116ed38b7376fba412",
            "upstream_version": "6.18.33",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.18.56"
          },
          "1:6.18.34-1+rpt1": {
            "linux_commit": "c8c7494100e99ee05b11aaa4f0588a223a63d1af",
            "upstream_version": "6.18.34",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.18.56"
          },
          "1:6.18.39-1+rpt1": {
            "linux_commit": "60ea684a8ace97bb0db1a16e20753bdd6ab371ff",
            "upstream_version": "6.18.39",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.18.56"
          },
          "1:6.18.50-1+rpt1": {
            "linux_commit": "cff533aec2fa601846766b32ff57204e0a61bed7",
            "upstream_version": "6.18.50",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": "6.18.56"
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-98773"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/9742905d9ed5bf23ebe4c100dec80b6bc50fb522"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/a0ed07b5bbb2d8fcef86810453216070691816e7"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/420ca35af891d33522cc08504768ccd60a4c450a"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/dc614d6bc991740d41d5a99ac7765c4b675dda88"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-10-18T15:54:51Z"
  }
}