CVE-2026-98573

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: net: skbuff: fix pull-bound underflow in skb_checksum_setup_ipv6() skb_maybe_pull_tail() subtracts skb_headlen(skb) from the unsigned max argument and passes the result to __pskb_pull_tail() as a signed int. The function does not ensure that max is at least skb_headlen(skb). This can happen while parsing IPv6 extension headers when an skb already has a linear area larger than MAX_IPV6_HDR_LEN. Once the parser needs data beyond the linear area, max - skb_headlen(skb) wraps and is converted to a negative delta. __pskb_pull_tail() then passes that negative length to skb_copy_bits(), where it can become a very large copy length. Pass the requested length itself as the pull bound at the three extension-header call sites, so the delta can no longer go negative.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-10-18 16:17:09.587000

Last modified

2026-10-19 10:19:15.453000

View original CVE JSON

{
  "id": "CVE-2026-98573",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-18T16:17:09.587",
  "lastModified": "2026-10-19T10:19:15.453",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: skbuff: fix pull-bound underflow in skb_checksum_setup_ipv6()\n\nskb_maybe_pull_tail() subtracts skb_headlen(skb) from the unsigned max\nargument and passes the result to __pskb_pull_tail() as a signed int.  The\nfunction does not ensure that max is at least skb_headlen(skb).\n\nThis can happen while parsing IPv6 extension headers when an skb already\nhas a linear area larger than MAX_IPV6_HDR_LEN.  Once the parser needs data\nbeyond the linear area, max - skb_headlen(skb) wraps and is converted to a\nnegative delta.  __pskb_pull_tail() then passes that negative length to\nskb_copy_bits(), where it can become a very large copy length.\n\nPass the requested length itself as the pull bound at the three\nextension-header call sites, so the delta can no longer go negative."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/core/skbuff.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "9c4e432132a97b82edf28fa172c39f743e6bfb26",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "718747afa5463d9cc5fd9a09f03b2a492edd9b78",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "a0ad0473c09d2e947aecac5c82e637ec85924b12",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "b2da5ed3d8c75e1b729a21b6d3beaed415e263f6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "6c28c31f051dbf49c71ba7ab7bb9bc905fa1d14b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "cfa643f2ca36c6f913fe1a2ceb12412ebb0fd962",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "d7f474226809471dc7877435e9c492cc914df0bf",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "1431fb31ecbaba1b5718006128f0f2ed0b94e1c3",
              "lessThan": "3b4e0b0c008a8c1b474730248cd5b873026c74bd",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/core/skbuff.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3.13",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "3.13",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.271",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.222",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.189",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.158",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.112",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.55",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.9",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/3b4e0b0c008a8c1b474730248cd5b873026c74bd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6c28c31f051dbf49c71ba7ab7bb9bc905fa1d14b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/718747afa5463d9cc5fd9a09f03b2a492edd9b78",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/9c4e432132a97b82edf28fa172c39f743e6bfb26",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a0ad0473c09d2e947aecac5c82e637ec85924b12",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b2da5ed3d8c75e1b729a21b6d3beaed415e263f6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cfa643f2ca36c6f913fe1a2ceb12412ebb0fd962",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d7f474226809471dc7877435e9c492cc914df0bf",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}