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CVE-2026-64566

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: propagate SKBFL_SHARED_FRAG in iptfs_skb_add_frags() When iptfs_skb_add_frags() copies frag references from the source frag walk into a new SKB, it increments the page reference count via __skb_frag_ref() but does not propagate SKBFL_SHARED_FRAG to the destination SKB's skb_shinfo->flags. If the source SKB carries shared frags (e.g. from a page-pool backed receive path), the new inner SKB will appear to ESP as having privately owned frags. A subsequent esp_input() call for a nested transport-mode SA then takes the no-COW fast path and decrypts in place, writing over pages that are still referenced by the outer IPTFS SKB. This causes kernel-visible memory corruption and can trigger a panic. All other frag-transfer helpers in the kernel (skb_try_coalesce, skb_gro_receive, __pskb_copy_fclone, skb_shift, skb_segment) correctly propagate SKBFL_SHARED_FRAG; align iptfs_skb_add_frags() with this convention by setting the flag inside the loop immediately after __skb_frag_ref() and nr_frags++, so every exit path that attaches a frag unconditionally propagates SKBFL_SHARED_FRAG.

Severity
CRITICAL
CVSS score
9.8 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-08-05 08:16:36.140000
Last modified
2026-11-03 18:15:39.353000
View original CVE JSON
{
  "id": "CVE-2026-64566",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-05T08:16:36.140",
  "lastModified": "2026-11-03T18:15:39.353",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: iptfs: propagate SKBFL_SHARED_FRAG in iptfs_skb_add_frags()\n\nWhen iptfs_skb_add_frags() copies frag references from the source\nfrag walk into a new SKB, it increments the page reference count via\n__skb_frag_ref() but does not propagate SKBFL_SHARED_FRAG to the\ndestination SKB's skb_shinfo->flags.\n\nIf the source SKB carries shared frags (e.g. from a page-pool backed\nreceive path), the new inner SKB will appear to ESP as having privately\nowned frags.  A subsequent esp_input() call for a nested transport-mode\nSA then takes the no-COW fast path and decrypts in place, writing over\npages that are still referenced by the outer IPTFS SKB.  This causes\nkernel-visible memory corruption and can trigger a panic.\n\nAll other frag-transfer helpers in the kernel (skb_try_coalesce,\nskb_gro_receive, __pskb_copy_fclone, skb_shift, skb_segment) correctly\npropagate SKBFL_SHARED_FRAG; align iptfs_skb_add_frags() with this\nconvention by setting the flag inside the loop immediately after\n__skb_frag_ref() and nr_frags++, so every exit path that attaches a frag\nunconditionally propagates SKBFL_SHARED_FRAG."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/xfrm/xfrm_iptfs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "lessThan": "d8aaf06b29f5a0b6186cf68d21c7d63678ee3891",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "lessThan": "ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "lessThan": "430ea57d6daf765e88f90046afbfd1e071cb7200",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/xfrm/xfrm_iptfs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.14",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.14",
              "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
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/430ea57d6daf765e88f90046afbfd1e071cb7200",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d8aaf06b29f5a0b6186cf68d21c7d63678ee3891",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}