{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "37745918e0e7575bc40f38da93a99b9fa6406224"
            },
            {
              "fixed": "d0e19932875746118e298b4c974f3b2d4aeb16fc"
            },
            {
              "fixed": "5260e195c53e898a4a76527d4bb2178f31795e78"
            },
            {
              "fixed": "42c6543ff27ea280334244458d4f52ec7133cc05"
            },
            {
              "fixed": "21e19688433452dfbbbe6b2bb670dea6eb92f0f6"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.12.0"
            },
            {
              "fixed": "6.12.103"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.44"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74504.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: seq: Fix division by zero in initialize_timer()\n\nA userspace-driven ALSA timer (SND_UTIMER) lets an unprivileged user set\nthe backing snd_timer's hardware resolution to an arbitrary 64-bit value\nvia SNDRV_TIMER_IOCTL_CREATE. snd_utimer_create() only rejects zero.\n\nWhen such a timer is bound to a sequencer queue, initialize_timer()\ncomputes the tick period as\n\n\ttmr-\u003eticks = 1000000000 / (r * freq);\n\nwhere r is that user-controlled resolution and freq is the sequencer\nupdate rate in Hz, clamped to MIN_FREQUENCY..MAX_FREQUENCY (10..6250).\nA resolution of 2^63 makes the 64-bit product r * freq wrap to zero for\nany even freq, including DEFAULT_FREQUENCY (1000), so the division faults\nwith a divide-by-zero.\n\nThe division runs under tmr-\u003elock with interrupts disabled, so the oops\nleaves the spinlock held and hangs the CPU. It is reachable by an\nunprivileged user with access to /dev/snd/timer and /dev/snd/seq.\n\n  Oops: divide error: 0000 [#1] SMP KASAN PTI\n  CPU: 7 UID: 1000 PID: 456 Comm: alsa_seq_utimer Not tainted 7.2.0-rc4+\n  RIP: 0010:initialize_timer.constprop.0+0x20a/0x2d0\n   snd_seq_timer_start+0x15e/0x2b0\n   snd_seq_control_queue+0x56f/0xba0\n   snd_seq_write+0x3e0/0x730\n\nReject an overflowing product with check_mul_overflow() and fall back to\na single tick, which also avoids feeding a wrapped-but-nonzero divisor\n(e.g. 2^63 * 1000 mod 2^64 == 0, or other resolutions wrapping to a small\nvalue) into the period computation.",
  "id": "CVE-2026-74504",
  "modified": "2026-08-18T03:30:57.981880632Z",
  "published": "2026-08-15T12:27:28.829Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/21e19688433452dfbbbe6b2bb670dea6eb92f0f6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/42c6543ff27ea280334244458d4f52ec7133cc05"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5260e195c53e898a4a76527d4bb2178f31795e78"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d0e19932875746118e298b4c974f3b2d4aeb16fc"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74504.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74504"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "ALSA: seq: Fix division by zero in initialize_timer()"
}