{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "60b3013cdaf3fa8a17243ca46b19db3cbe08d943"
            },
            {
              "fixed": "60af1fd82983c26604102e63a3fcc822c186cceb"
            },
            {
              "fixed": "0a57320f71941d4e0b1307453c9a1f0939afe666"
            },
            {
              "fixed": "14147b7963685957839c76ba8094924e22777d79"
            },
            {
              "fixed": "a1288cd700f721c1a119c4f1e8efa234e59caada"
            },
            {
              "fixed": "70d86e355c564b5510fde61361df014f5476c83e"
            },
            {
              "fixed": "372f33ebed747d91870f57c0a2e62884a870bffa"
            },
            {
              "fixed": "bde742b076cbe26ecc89c8c68c76ae076a524d02"
            },
            {
              "fixed": "96d47e40bf9db4a9efd5c8fb53287a508d165f14"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.35"
            },
            {
              "fixed": "5.10.259"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.210"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.176"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.143"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.94"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.36"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.0.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53194.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nUSB: serial: kl5kusb105: fix bulk-out buffer overflow\n\nklsi_105_prepare_write_buffer() is called by the generic write path\nwith the bulk-out buffer and its size (bulk_out_size, 64 bytes). It\nstores a two-byte length header at the start of the buffer and copies\nthe payload from the write fifo starting at buf + KLSI_HDR_LEN, but\npasses the full buffer size as the number of bytes to copy:\n\n  count = kfifo_out_locked(\u0026port-\u003ewrite_fifo, buf + KLSI_HDR_LEN,\n                           size, \u0026port-\u003elock);\n\nWhen the fifo holds at least size bytes, size bytes are copied starting\ntwo bytes into the size-byte buffer, writing KLSI_HDR_LEN bytes past its\nend. Copy at most size - KLSI_HDR_LEN bytes instead, leaving room for\nthe header as safe_serial already does.\n\nWriting bulk_out_size or more bytes to the tty triggers a slab\nout-of-bounds write, observed with KASAN by emulating the device with\ndummy_hcd and raw-gadget:\n\n  BUG: KASAN: slab-out-of-bounds in kfifo_copy_out+0x83/0xc0\n  Write of size 64 at addr ffff888112c62202 by task python3\n   kfifo_copy_out\n   klsi_105_prepare_write_buffer [kl5kusb105]\n   usb_serial_generic_write_start [usbserial]\n  Allocated by task 139:\n   usb_serial_probe [usbserial]\n  The buggy address is located 2 bytes inside of allocated 64-byte region\n\nThe out-of-bounds write no longer occurs with this change applied.",
  "id": "CVE-2026-53194",
  "modified": "2026-07-08T05:39:04.624521067Z",
  "published": "2026-06-25T08:39:05.017Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0a57320f71941d4e0b1307453c9a1f0939afe666"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/14147b7963685957839c76ba8094924e22777d79"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/372f33ebed747d91870f57c0a2e62884a870bffa"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/60af1fd82983c26604102e63a3fcc822c186cceb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/70d86e355c564b5510fde61361df014f5476c83e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/96d47e40bf9db4a9efd5c8fb53287a508d165f14"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a1288cd700f721c1a119c4f1e8efa234e59caada"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bde742b076cbe26ecc89c8c68c76ae076a524d02"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53194.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/security/cve/CVE-2026-53194"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53194.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53194"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492703"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "USB: serial: kl5kusb105: fix bulk-out buffer overflow"
}