{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a"
            },
            {
              "fixed": "02d9c5b0b5553a391448b6d655262bd829f90234"
            },
            {
              "fixed": "3f7f8bae0d52cbd07ab04b76b6aac89ef98ee9f6"
            },
            {
              "fixed": "66194c2575a4f567577ae70b1d7561163ce791a6"
            },
            {
              "fixed": "a82c1bce2d1299dd3c686a8fe48cf75b79a403c7"
            },
            {
              "fixed": "3178b62e2e31bab39f63d4c8e54bf4ee0a425627"
            },
            {
              "fixed": "3afa2e67f3523a980a2f90fd63c22322ac2b9ce0"
            },
            {
              "fixed": "7594a6464873d90fd229e5b94cdd3b92c9feabed"
            },
            {
              "fixed": "45424e871abf2a152e247a9cff78359f18dd95c0"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.31"
            },
            {
              "fixed": "5.10.253"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.168"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.134"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.81"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.22"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31778.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: caiaq: fix stack out-of-bounds read in init_card\n\nThe loop creates a whitespace-stripped copy of the card shortname\nwhere `len \u003c sizeof(card-\u003eid)` is used for the bounds check. Since\nsizeof(card-\u003eid) is 16 and the local id buffer is also 16 bytes,\nwriting 16 non-space characters fills the entire buffer,\noverwriting the terminating nullbyte.\n\nWhen this non-null-terminated string is later passed to\nsnd_card_set_id() -\u003e copy_valid_id_string(), the function scans\nforward with `while (*nid \u0026\u0026 ...)` and reads past the end of the\nstack buffer, reading the contents of the stack.\n\nA USB device with a product name containing many non-ASCII, non-space\ncharacters (e.g. multibyte UTF-8) will reliably trigger this as follows:\n\n  BUG: KASAN: stack-out-of-bounds in copy_valid_id_string\n       sound/core/init.c:696 [inline]\n  BUG: KASAN: stack-out-of-bounds in snd_card_set_id_no_lock+0x698/0x74c\n       sound/core/init.c:718\n\nThe off-by-one has been present since commit bafeee5b1f8d (\"ALSA:\nsnd_usb_caiaq: give better shortname\") from June 2009 (v2.6.31-rc1),\nwhich first introduced this whitespace-stripping loop. The original\ncode never accounted for the null terminator when bounding the copy.\n\nFix this by changing the loop bound to `sizeof(card-\u003eid) - 1`,\nensuring at least one byte remains as the null terminator.",
  "id": "CVE-2026-31778",
  "modified": "2026-07-08T05:37:40.510151399Z",
  "published": "2026-05-01T14:15:05.804Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/02d9c5b0b5553a391448b6d655262bd829f90234"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3178b62e2e31bab39f63d4c8e54bf4ee0a425627"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3afa2e67f3523a980a2f90fd63c22322ac2b9ce0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3f7f8bae0d52cbd07ab04b76b6aac89ef98ee9f6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/45424e871abf2a152e247a9cff78359f18dd95c0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/66194c2575a4f567577ae70b1d7561163ce791a6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7594a6464873d90fd229e5b94cdd3b92c9feabed"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a82c1bce2d1299dd3c686a8fe48cf75b79a403c7"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31778.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31778"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "ALSA: caiaq: fix stack out-of-bounds read in init_card"
}