{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.176-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.85-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.19.14-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  ALSA: ctxfi: Limit PTP to a single page  Commit 391e69143d0a increased CT_PTP_NUM from 1 to 4 to support 256 playback streams, but the additional pages are not used by the card correctly. The CT20K2 hardware already has multiple VMEM_PTPAL registers, but using them separately would require refactoring the entire virtual memory allocation logic.  ct_vm_map() always uses PTEs in vm-\u003eptp[0].area regardless of CT_PTP_NUM. On AMD64 systems, a single PTP covers 512 PTEs (2M). When aggregate memory allocations exceed this limit, ct_vm_map() tries to access beyond the allocated space and causes a page fault:    BUG: unable to handle page fault for address: ffffd4ae8a10a000   Oops: Oops: 0002 [#1] SMP PTI   RIP: 0010:ct_vm_map+0x17c/0x280 [snd_ctxfi]   Call Trace:   atc_pcm_playback_prepare+0x225/0x3b0   ct_pcm_playback_prepare+0x38/0x60   snd_pcm_do_prepare+0x2f/0x50   snd_pcm_action_single+0x36/0x90   snd_pcm_action_nonatomic+0xbf/0xd0   snd_pcm_ioctl+0x28/0x40   __x64_sys_ioctl+0x97/0xe0   do_syscall_64+0x81/0x610   entry_SYSCALL_64_after_hwframe+0x76/0x7e  Revert CT_PTP_NUM to 1. The 256 SRC_RESOURCE_NUM and playback_count remain unchanged.",
  "id": "DEBIAN-CVE-2026-31602",
  "modified": "2026-09-14T16:47:37.090751570Z",
  "published": "2026-04-24T15:16:39.263Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-31602"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-31602"
  ]
}