cve-2026-99999

CRITICAL CVSS 9.3 nvd
Description

In the Linux kernel, the following vulnerability has been resolved: ipv4: validate checksum_start before completing checksum If a packet with bad checksum metadata gets into the ipv4 stack, skb_checksum_help can corrupt the network header and cause a bunch of mischief. This was discovered and reported by Paulos, and has been reporoduced by others independently since. We really shouldn't allow such packets in, but as a defence in depth measure, let's also check before we complete the checksum. A more complete validation at input is forthcoming, but needs more work.

Timeline
Published
2026-10-15
Last Modified
2026-10-19
CVSS Details
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
Affected Products

No product information available.

Weaknesses (CWE)
CVSS metrics
Version Base Severity Vector Exploitability Impact Source
3.1 9.3 CRITICAL CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H 2.5 6.0 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD metadata
NVD status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
Linked Vulnerabilities

{
  "cvss": 9.3,
  "datePublished": "2026-10-15T13:17:14.137",
  "dateUpdated": "2026-10-19T22:17:28.667",
  "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: validate checksum_start before completing checksum\n\nIf a packet with bad checksum metadata gets into the ipv4 stack,\nskb_checksum_help can corrupt the network header and cause a bunch of\nmischief.\n\nThis was discovered and reported by Paulos, and has been reporoduced\nby others independently since.\n\nWe really shouldn't allow such packets in, but as a defence\nin depth measure, let's also check before we complete the checksum.\n\nA more complete validation at input is forthcoming, but needs more work.",
  "id": "CVE-2026-99999",
  "raw": {
    "affected": [
      {
        "affectedData": [
          {
            "defaultStatus": "unaffected",
            "product": "Linux",
            "programFiles": [
              "include/net/ip.h",
              "net/bridge/netfilter/nf_conntrack_bridge.c",
              "net/ipv4/ip_output.c",
              "net/netfilter/nfnetlink_queue.c",
              "net/netfilter/xt_CHECKSUM.c",
              "net/xfrm/xfrm_output.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "lessThan": "a464d950f31c89565cbaae038cc60db04fe01956",
                "status": "affected",
                "version": "f43798c27684ab925adde7d8acc34c78c6e50df8",
                "versionType": "git"
              },
              {
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                "status": "affected",
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                "versionType": "git"
              },
              {
                "lessThan": "94524b7b32691de2e2ce162c04d6cbc9106e5cbf",
                "status": "affected",
                "version": "f43798c27684ab925adde7d8acc34c78c6e50df8",
                "versionType": "git"
              },
              {
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                "status": "affected",
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              },
              {
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                "status": "affected",
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              },
              {
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                "versionType": "git"
              },
              {
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                "status": "affected",
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                "versionType": "git"
              },
              {
                "lessThan": "6785011f8b16abf40b1e9d8b2e332232b3e68822",
                "status": "affected",
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                "versionType": "git"
              }
            ]
          },
          {
            "defaultStatus": "affected",
            "product": "Linux",
            "programFiles": [
              "include/net/ip.h",
              "net/bridge/netfilter/nf_conntrack_bridge.c",
              "net/ipv4/ip_output.c",
              "net/netfilter/nfnetlink_queue.c",
              "net/netfilter/xt_CHECKSUM.c",
              "net/xfrm/xfrm_output.c"
            ],
            "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
            "vendor": "Linux",
            "versions": [
              {
                "status": "affected",
                "version": "2.6.27"
              },
              {
                "lessThan": "2.6.27",
                "status": "unaffected",
                "version": "0",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "5.10.*",
                "status": "unaffected",
                "version": "5.10.272",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "5.15.*",
                "status": "unaffected",
                "version": "5.15.223",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.1.*",
                "status": "unaffected",
                "version": "6.1.190",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.6.*",
                "status": "unaffected",
                "version": "6.6.159",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.12.*",
                "status": "unaffected",
                "version": "6.12.113",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "6.18.*",
                "status": "unaffected",
                "version": "6.18.57",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "7.2.*",
                "status": "unaffected",
                "version": "7.2.11",
                "versionType": "semver"
              },
              {
                "lessThanOrEqual": "*",
                "status": "unaffected",
                "version": "7.3",
                "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\nipv4: validate checksum_start before completing checksum\n\nIf a packet with bad checksum metadata gets into the ipv4 stack,\nskb_checksum_help can corrupt the network header and cause a bunch of\nmischief.\n\nThis was discovered and reported by Paulos, and has been reporoduced\nby others independently since.\n\nWe really shouldn't allow such packets in, but as a defence\nin depth measure, let's also check before we complete the checksum.\n\nA more complete validation at input is forthcoming, but needs more work."
      }
    ],
    "id": "CVE-2026-99999",
    "lastModified": "2026-10-19T22:17:28.667",
    "metrics": {
      "cvssMetricV31": [
        {
          "cvssData": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 9.3,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "exploitabilityScore": 2.5,
          "impactScore": 6.0,
          "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
          "type": "Secondary"
        }
      ],
      "ssvcV203": [
        {
          "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "ssvcData": {
            "id": "CVE-2026-99999",
            "options": [
              {
                "exploitation": "none"
              },
              {
                "automatable": "no"
              },
              {
                "technicalImpact": "total"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-10-16T15:49:03.519458Z",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2026-10-15T13:17:14.137",
    "references": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/0fab003ef4698e0628060a45a48f14b43ba2a40a"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://git.kernel.org/stable/c/32a8b0adaa18e52aaa0b246b5ffe683075354dbb"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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      },
      {
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      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://pwn.ai/blog/pwnescape"
      },
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "url": "https://vercel.com/blog/findings-from-the-1-million-dollar-vercel-sandbox-challenge"
      },
      {
        "source": "af854a3a-2127-422b-91ae-364da2661108",
        "url": "http://www.openwall.com/lists/oss-security/2026/10/15/5"
      }
    ],
    "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "vulnStatus": "Received",
    "weaknesses": [
      {
        "description": [
          {
            "lang": "en",
            "value": "CWE-20"
          }
        ],
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ]
  },
  "severity": "CRITICAL",
  "source": "nvd",
  "title": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: validate checksum_start before completing ..."
}
Enrichment data
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