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CVE-2026-68127

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: ila: reload IPv6 header after pskb_may_pull in checksum adjust ila_csum_adjust_transport() caches ip6h = ipv6_hdr(skb) before calling pskb_may_pull(). On a non-linear skb whose transport header sits in a page fragment, pskb_may_pull() can call __pskb_pull_tail() / pskb_expand_head() and free the old skb head, leaving ip6h dangling; the following get_csum_diff(ip6h, p) then reads freed memory. ila_update_ipv6_locator() uses ip6h (and the iaddr derived from it) again after the csum-adjust call and additionally writes the new locator through that pointer. Impact: a remote IPv6 packet routed through a configured ILA csum-adjust-transport route or receive-side mapping triggers a slab-use-after-free in ila_update_ipv6_locator() (KASAN). The route or mapping requires CAP_NET_ADMIN to configure, but trigger packets are unauthenticated once it exists. Reload ip6h after each pskb_may_pull() in ila_csum_adjust_transport() before the csum-diff read. In ila_update_ipv6_locator() only the ILA_CSUM_ADJUST_TRANSPORT case pulls the skb, so reload ip6h and iaddr in that case alone before the destination-address write; the neutral-map modes never pull and keep their cached pointers.

Severity
CRITICAL
CVSS score
9.8 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-10 13:19:57.940000
Last modified
2026-10-19 21:17:52.650000
View original CVE JSON
{
  "id": "CVE-2026-68127",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-10T13:19:57.940",
  "lastModified": "2026-10-19T21:17:52.650",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nila: reload IPv6 header after pskb_may_pull in checksum adjust\n\nila_csum_adjust_transport() caches ip6h = ipv6_hdr(skb) before calling\npskb_may_pull(). On a non-linear skb whose transport header sits in a page\nfragment, pskb_may_pull() can call __pskb_pull_tail() / pskb_expand_head()\nand free the old skb head, leaving ip6h dangling; the following\nget_csum_diff(ip6h, p) then reads freed memory. ila_update_ipv6_locator()\nuses ip6h (and the iaddr derived from it) again after the csum-adjust\ncall and additionally writes the new locator through that pointer.\n\nImpact: a remote IPv6 packet routed through a configured ILA\ncsum-adjust-transport route or receive-side mapping triggers a\nslab-use-after-free in ila_update_ipv6_locator() (KASAN). The route or\nmapping requires CAP_NET_ADMIN to configure, but trigger packets are\nunauthenticated once it exists.\n\nReload ip6h after each pskb_may_pull() in ila_csum_adjust_transport()\nbefore the csum-diff read. In ila_update_ipv6_locator() only the\nILA_CSUM_ADJUST_TRANSPORT case pulls the skb, so reload ip6h and iaddr in\nthat case alone before the destination-address write; the neutral-map\nmodes never pull and keep their cached pointers."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/ipv6/ila/ila_common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "e451a904606c571f731ef7a06b3398619dce5300",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "1eadcb43893b897ade85ac5bf5c618054bc3c655",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "ba353caafb06ccee57b78d3254e3cebf1dea4a93",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "896a9512d0d83c2a4b357e5585b7b62a8e3f95c1",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "7097a0280b178237265681be66d1bef11d15894b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "472aba2603ca74c4f7722cb0c0296942b0776b8d",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "c6a13ae00dab3a1a8c7cf2f843f0fc9e8d4b0ccc",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "33f11d16142b06588eedfc1dd8cf93790979a712",
              "lessThan": "92d3817649df2b0b6a008a686c8275c88d7ef594",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/ipv6/ila/ila_common.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "4.5",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "4.5",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.265",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.216",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.183",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.148",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.101",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.42",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.6",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T15:44:18.440814Z",
          "id": "CVE-2026-68127",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1eadcb43893b897ade85ac5bf5c618054bc3c655",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/472aba2603ca74c4f7722cb0c0296942b0776b8d",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/7097a0280b178237265681be66d1bef11d15894b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/896a9512d0d83c2a4b357e5585b7b62a8e3f95c1",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    {
      "url": "https://git.kernel.org/stable/c/92d3817649df2b0b6a008a686c8275c88d7ef594",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ba353caafb06ccee57b78d3254e3cebf1dea4a93",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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    }
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}