{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-31602",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-31602",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-04-24T14:42:25.935Z",
    "updatedAt": "2026-08-05T12:23:44.562Z",
    "importedAt": "2026-10-24T01:58:02.025Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "ALSA: ctxfi: Limit PTP to a single page",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: ctxfi: Limit PTP to a single page\n\nCommit 391e69143d0a increased CT_PTP_NUM from 1 to 4 to support 256\nplayback streams, but the additional pages are not used by the card\ncorrectly. The CT20K2 hardware already has multiple VMEM_PTPAL\nregisters, but using them separately would require refactoring the\nentire virtual memory allocation logic.\n\nct_vm_map() always uses PTEs in vm->ptp[0].area regardless of\nCT_PTP_NUM. On AMD64 systems, a single PTP covers 512 PTEs (2M). When\naggregate memory allocations exceed this limit, ct_vm_map() tries to\naccess beyond the allocated space and causes a page fault:\n\n  BUG: unable to handle page fault for address: ffffd4ae8a10a000\n  Oops: Oops: 0002 [#1] SMP PTI\n  RIP: 0010:ct_vm_map+0x17c/0x280 [snd_ctxfi]\n  Call Trace:\n  atc_pcm_playback_prepare+0x225/0x3b0\n  ct_pcm_playback_prepare+0x38/0x60\n  snd_pcm_do_prepare+0x2f/0x50\n  snd_pcm_action_single+0x36/0x90\n  snd_pcm_action_nonatomic+0xbf/0xd0\n  snd_pcm_ioctl+0x28/0x40\n  __x64_sys_ioctl+0x97/0xe0\n  do_syscall_64+0x81/0x610\n  entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nRevert CT_PTP_NUM to 1. The 256 SRC_RESOURCE_NUM and playback_count\nremain unchanged.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "c5908160e17cb56e1f61fbaee08adc21083f4933"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "de8016fb0904d68ac886e375069535996baa42ee"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "2b4331c08c0b385598b4d8ccd71e93ab3f4b2578"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "452894005b4abe141b11fe01e7bfe152e6d3860f"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "365c36e1a126c6aa1aecedd3a351bcabc66f0c29"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3fd0685d7fef68c2d8a04876bcf9eaa0724ad6a5"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b7f5ecd13cce8c2f8fa5a84c9aab65997142577e"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ad9011a795407093dcf507f6e5da1828987b4b47"
            },
            {
              "version": "391e69143d0a05f960e3ab39a8c26b7b230bb8a9",
              "status": "affected",
              "versionType": "git",
              "lessThan": "e9418da50d9e5c496c22fe392e4ad74c038a94eb"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "3.2",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "3.2"
            },
            {
              "version": "5.10.258",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.209",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.175",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.136",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.83",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.24",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "6.19.14",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "version": "7.0.1",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.0.*"
            },
            {
              "version": "7.1",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}