FKIE_CVE-2026-63893

Vulnerability from fkie_nvd - Published: 2026-07-19 16:17 - Updated: 2026-07-20 15:16
Severity
8.1 (High) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() entry->value is u32 and entry->length is u16; the sum is performed in u32 and wraps. A malicious XDomain peer can pick value = 0xffffff00, length = 0x100 so the sum 0x100000000 wraps to 0 and passes the > block_len check. tb_property_parse() then passes entry->value to parse_dwdata() as a dword offset into the property block, reading attacker-directed memory far past the allocation. For TEXT-typed entries with the "deviceid" or "vendorid" keys this lands in xd->device_name / xd->vendor_name and is readable back via the per-XDomain device_name / vendor_name sysfs attributes; the leak is NUL-bounded (kstrdup() stops at the first zero byte) and untargeted (the attacker picks a delta, not an absolute address). DATA-typed entries are parsed into property->value.data but not generically surfaced to userspace. Use check_add_overflow() so a wrapped sum is rejected.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/01deda0152066c6c955f0619114ea6afa070aaec
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/31b98e503ecca8077e5247253dd5425ab84bc96d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5c06a3043ad944f087bb2ae0aae28d820bb9f460
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6a63623621639acbb39bc2d9fb09559681716695
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/8d4a758b407ab3de3be86d1ceadfa35d717d30c7
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/9fee50c4e1e42f6d3cbe30df584f9f648f626071
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a47784aee77f33f786dc5d7375db821bdae68792
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/thunderbolt/property.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "6a63623621639acbb39bc2d9fb09559681716695",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            },
            {
              "lessThan": "e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            },
            {
              "lessThan": "9fee50c4e1e42f6d3cbe30df584f9f648f626071",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            },
            {
              "lessThan": "8d4a758b407ab3de3be86d1ceadfa35d717d30c7",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            },
            {
              "lessThan": "5c06a3043ad944f087bb2ae0aae28d820bb9f460",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            },
            {
              "lessThan": "31b98e503ecca8077e5247253dd5425ab84bc96d",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            },
            {
              "lessThan": "a47784aee77f33f786dc5d7375db821bdae68792",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            },
            {
              "lessThan": "01deda0152066c6c955f0619114ea6afa070aaec",
              "status": "affected",
              "version": "cdae7c07e3e3509eaabc18c1640a55dc5b99c179",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/thunderbolt/property.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.15"
            },
            {
              "lessThan": "4.15",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.259",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.210",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.176",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.143",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.93",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.35",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.12",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: property: Reject u32 wrap in tb_property_entry_valid()\n\nentry-\u003evalue is u32 and entry-\u003elength is u16; the sum is performed in\nu32 and wraps.  A malicious XDomain peer can pick\nvalue = 0xffffff00, length = 0x100 so the sum 0x100000000 wraps to 0\nand passes the \u003e block_len check.  tb_property_parse() then passes\nentry-\u003evalue to parse_dwdata() as a dword offset into the property\nblock, reading attacker-directed memory far past the allocation.\n\nFor TEXT-typed entries with the \"deviceid\" or \"vendorid\" keys this\nlands in xd-\u003edevice_name / xd-\u003evendor_name and is readable back via\nthe per-XDomain device_name / vendor_name sysfs attributes; the leak\nis NUL-bounded (kstrdup() stops at the first zero byte) and\nuntargeted (the attacker picks a delta, not an absolute address).\nDATA-typed entries are parsed into property-\u003evalue.data but not\ngenerically surfaced to userspace.\n\nUse check_add_overflow() so a wrapped sum is rejected."
    }
  ],
  "id": "CVE-2026-63893",
  "lastModified": "2026-07-20T15:16:54.537",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "ADJACENT_NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.2,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-07-19T16:17:06.710",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/01deda0152066c6c955f0619114ea6afa070aaec"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/31b98e503ecca8077e5247253dd5425ab84bc96d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5c06a3043ad944f087bb2ae0aae28d820bb9f460"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6a63623621639acbb39bc2d9fb09559681716695"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8d4a758b407ab3de3be86d1ceadfa35d717d30c7"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/9fee50c4e1e42f6d3cbe30df584f9f648f626071"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a47784aee77f33f786dc5d7375db821bdae68792"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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