Vulnerability-Lookup

FKIE_CVE-2026-64566

Vulnerability from fkie_nvd - Published: 2026-08-05 08:16 - Updated: 2026-08-08 15:16

Severity

9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Summary

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.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/430ea57d6daf765e88f90046afbfd1e071cb7200
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d8aaf06b29f5a0b6186cf68d21c7d63678ee3891
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/xfrm_iptfs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d8aaf06b29f5a0b6186cf68d21c7d63678ee3891",
              "status": "affected",
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "versionType": "git"
            },
            {
              "lessThan": "ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0",
              "status": "affected",
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "versionType": "git"
            },
            {
              "lessThan": "430ea57d6daf765e88f90046afbfd1e071cb7200",
              "status": "affected",
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/xfrm_iptfs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.14"
            },
            {
              "lessThan": "6.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2-rc4",
              "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\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\u0027s skb_shinfo-\u003eflags.\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."
    }
  ],
  "id": "CVE-2026-64566",
  "lastModified": "2026-08-08T15:16:31.713",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-05T08:16:36.140",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "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"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-64566 (GCVE-0-2026-64566)

Vulnerability from cvelistv5 – Published: 2026-08-05 08:06 – Updated: 2026-08-08 15:13

Title

xfrm: iptfs: propagate SKBFL_SHARED_FRAG in iptfs_skb_add_frags()

Summary

Severity

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux

References

3 references

URL	Tags
https://git.kernel.org/stable/c/d8aaf06b29f5a0b61…
https://git.kernel.org/stable/c/ffd64e0717efd83fb…
https://git.kernel.org/stable/c/430ea57d6daf765e8…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7 , < d8aaf06b29f5a0b6186cf68d21c7d63678ee3891 (git) Affected: 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7 , < ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0 (git) Affected: 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7 , < 430ea57d6daf765e88f90046afbfd1e071cb7200 (git)
Linux	Linux	Affected: 6.14 Unaffected: 0 , < 6.14 (semver) Unaffected: 6.18.42 , ≤ 6.18.* (semver) Unaffected: 7.1.6 , ≤ 7.1.* (semver) Unaffected: 7.2-rc4 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/xfrm_iptfs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "d8aaf06b29f5a0b6186cf68d21c7d63678ee3891",
              "status": "affected",
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "versionType": "git"
            },
            {
              "lessThan": "ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0",
              "status": "affected",
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "versionType": "git"
            },
            {
              "lessThan": "430ea57d6daf765e88f90046afbfd1e071cb7200",
              "status": "affected",
              "version": "5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/xfrm/xfrm_iptfs.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.14"
            },
            {
              "lessThan": "6.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2-rc4",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.42",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.6",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2-rc4",
                  "versionStartIncluding": "6.14",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "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\u0027s skb_shinfo-\u003eflags.\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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The flaw is on the IPsec IPTFS receive path: inbound ESP packets hit xfrm_input \u2192 iptfs_input \u2192 iptfs_skb_add_frags, then reinjected inner packets reach nested transport-mode esp_input(); a remote IPTFS/IPsec peer triggers it with network packets.\nAC:L - On a host with IPTFS plus a nested transport-mode SA, the peer fully controls packet sizes and ESP payloads that take the frag-share path and drive in-place decrypt; no race or attacker-uncontrollable memory layout is required.\nPR:N - Exploitation is by a remote IPsec peer sending packets to an already-configured IPTFS endpoint; no local account or capability on the target is required, and SA presence is a deployment precondition rather than an attacker privilege.\nUI:N - Packets are processed in softirq/NAPI receive context with no victim action such as mounting, opening a file, or otherwise interacting with the system.\nS:U - Corruption is of shared skb/NIC fragment pages within the same kernel security authority; this is not a VM escape, IOMMU bypass, or cross-sandbox boundary crossing.\nC:H - Missing SKBFL_SHARED_FRAG lets nested esp_input() overwrite pages still referenced by the outer IPTFS skb and sibling inners, yielding attacker-influenced memory corruption that can be leveraged for information disclosure.\nI:H - In-place ESP decryption writes attacker-controlled plaintext into pages still held by other skbs, providing a memory-corruption write primitive capable of integrity compromise and control-flow impact.\nA:H - The same shared-page overwrite causes kernel-visible memory corruption and can panic/oops the host, fully denying availability."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-08T15:13:07.286Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/d8aaf06b29f5a0b6186cf68d21c7d63678ee3891"
        },
        {
          "url": "https://git.kernel.org/stable/c/ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0"
        },
        {
          "url": "https://git.kernel.org/stable/c/430ea57d6daf765e88f90046afbfd1e071cb7200"
        }
      ],
      "title": "xfrm: iptfs: propagate SKBFL_SHARED_FRAG in iptfs_skb_add_frags()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64566",
    "datePublished": "2026-08-05T08:06:18.645Z",
    "dateReserved": "2026-07-19T15:36:31.797Z",
    "dateUpdated": "2026-08-08T15:13:07.286Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

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FKIE_CVE-2026-64566

CVE-2026-64566 (GCVE-0-2026-64566)

Tags

Sightings

Nomenclature