Vulnerability-Lookup

FKIE_CVE-2026-72463

Vulnerability from fkie_nvd - Published: 2026-08-15 06:22 - Updated: 2026-08-17 06:19

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: Fix dev use-after-free in xfrm async resumption xfrm async resumption hold skb->dev refcnt until after transport_finish. However, xfrm_rcv_cb may modify skb->dev to tunnel dev without taking device reference, such as vti_rcv_cb. The subsequent async resumption will decrement the tunnel device's reference count, which lead to uaf of tunnel dev and refcnt leak of orig dev as below: unregister_netdevice: waiting for vti1 to become free. Usage count = -2 Stash the original skb->dev to fix refcnt imbalance. The new skb->dev set by xfrm_rcv_cb can race with device teardown. Extend rcu protection over xfrm_rcv_cb and transport_finish to prevent races.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/63a30015199912bd5055bead8001b1ae68a67cdb
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/xfrm4_input.c",
            "net/ipv6/xfrm6_input.c",
            "net/xfrm/xfrm_input.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "63a30015199912bd5055bead8001b1ae68a67cdb",
              "status": "affected",
              "version": "1c428b03840094410c5fb6a5db30640486bbbfcb",
              "versionType": "git"
            },
            {
              "lessThan": "8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff",
              "status": "affected",
              "version": "1c428b03840094410c5fb6a5db30640486bbbfcb",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4236c30b437b80f673b9e08c8fae38b8d471ac9e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f451b43c88bf2b9c038b414be580efee42e031b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5002beda5cac69d522dc54da0d5d463ed9c963d2",
              "versionType": "git"
            },
            {
              "lessThan": "6.13",
              "status": "affected",
              "version": "6.12.94",
              "versionType": "semver"
            },
            {
              "lessThan": "6.19",
              "status": "affected",
              "version": "6.18.23",
              "versionType": "semver"
            },
            {
              "lessThan": "6.20",
              "status": "affected",
              "version": "6.19.13",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/xfrm4_input.c",
            "net/ipv6/xfrm6_input.c",
            "net/xfrm/xfrm_input.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.0"
            },
            {
              "lessThan": "7.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "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: Fix dev use-after-free in xfrm async resumption\n\nxfrm async resumption hold skb-\u003edev refcnt until after transport_finish.\nHowever, xfrm_rcv_cb may modify skb-\u003edev to tunnel dev without taking\ndevice reference, such as vti_rcv_cb. The subsequent async resumption\nwill decrement the tunnel device\u0027s reference count, which lead to uaf\nof tunnel dev and refcnt leak of orig dev as below:\n\nunregister_netdevice: waiting for vti1 to become free. Usage count = -2\n\nStash the original skb-\u003edev to fix refcnt imbalance. The new skb-\u003edev set\nby xfrm_rcv_cb can race with device teardown. Extend rcu protection over\nxfrm_rcv_cb and transport_finish to prevent races."
    }
  ],
  "id": "CVE-2026-72463",
  "lastModified": "2026-08-17T06:19:14.040",
  "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": "2026-08-15T06:22:20.303",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/63a30015199912bd5055bead8001b1ae68a67cdb"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-72463 (GCVE-0-2026-72463)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:57 – Updated: 2026-08-17 05:44

Title

xfrm: Fix dev use-after-free in xfrm async resumption

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 mitre root

References

2 references

URL	Tags
https://git.kernel.org/stable/c/63a30015199912bd5…
https://git.kernel.org/stable/c/8045c0df98d4f14c5…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 1c428b03840094410c5fb6a5db30640486bbbfcb , < 63a30015199912bd5055bead8001b1ae68a67cdb (git) Affected: 1c428b03840094410c5fb6a5db30640486bbbfcb , < 8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff (git) Affected: 4236c30b437b80f673b9e08c8fae38b8d471ac9e (git) Affected: 0f451b43c88bf2b9c038b414be580efee42e031b (git) Affected: 5002beda5cac69d522dc54da0d5d463ed9c963d2 (git) Affected: 6.12.94 , < 6.13 (semver) Affected: 6.18.23 , < 6.19 (semver) Affected: 6.19.13 , < 6.20 (semver)
Linux	Linux	Affected: 7.0 Unaffected: 0 , < 7.0 (semver) Unaffected: 7.1.5 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/xfrm4_input.c",
            "net/ipv6/xfrm6_input.c",
            "net/xfrm/xfrm_input.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "63a30015199912bd5055bead8001b1ae68a67cdb",
              "status": "affected",
              "version": "1c428b03840094410c5fb6a5db30640486bbbfcb",
              "versionType": "git"
            },
            {
              "lessThan": "8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff",
              "status": "affected",
              "version": "1c428b03840094410c5fb6a5db30640486bbbfcb",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4236c30b437b80f673b9e08c8fae38b8d471ac9e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0f451b43c88bf2b9c038b414be580efee42e031b",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "5002beda5cac69d522dc54da0d5d463ed9c963d2",
              "versionType": "git"
            },
            {
              "lessThan": "6.13",
              "status": "affected",
              "version": "6.12.94",
              "versionType": "semver"
            },
            {
              "lessThan": "6.19",
              "status": "affected",
              "version": "6.18.23",
              "versionType": "semver"
            },
            {
              "lessThan": "6.20",
              "status": "affected",
              "version": "6.19.13",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/xfrm4_input.c",
            "net/ipv6/xfrm6_input.c",
            "net/xfrm/xfrm_input.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "7.0"
            },
            {
              "lessThan": "7.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "7.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "7.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.12.94",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.18.23",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.19.13",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: Fix dev use-after-free in xfrm async resumption\n\nxfrm async resumption hold skb-\u003edev refcnt until after transport_finish.\nHowever, xfrm_rcv_cb may modify skb-\u003edev to tunnel dev without taking\ndevice reference, such as vti_rcv_cb. The subsequent async resumption\nwill decrement the tunnel device\u0027s reference count, which lead to uaf\nof tunnel dev and refcnt leak of orig dev as below:\n\nunregister_netdevice: waiting for vti1 to become free. Usage count = -2\n\nStash the original skb-\u003edev to fix refcnt imbalance. The new skb-\u003edev set\nby xfrm_rcv_cb can race with device teardown. Extend rcu protection over\nxfrm_rcv_cb and transport_finish to prevent races."
        }
      ],
      "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 - Reachable from the network receive path: remote ESP/AH (or UDP-encapsulated IPsec) packets hit ip_rcv \u2192 xfrm4/xfrm6 protocol handlers \u2192 vti/xfrmi input \u2192 xfrm_input() \u2192 async crypto resume, on Internet-facing IPsec/VTI/xfrmi VPN gateways and cloud endpoints.\nAC:L - Once async decryption resumes (encap_type=-1), vti_rcv_cb/xfrmi_rcv_cb retarget skb-\u003edev and the stale dev_put is deterministic; the attacker controls packet rate/volume to drive -EINPROGRESS and can race netdev teardown, so no uncontrollable victim-only conditions apply.\nPR:N - No local account, shell, or capability on the victim is required\u2014only network-delivered IPsec traffic accepted by a pre-configured VTI/xfrmi gateway (e.g., VPN peer, site-to-site endpoint); administrative IPsec setup is deployment state, not attacker privilege on the host.\nUI:N - Exploitation is fully automated by sending IPsec packets; no victim interaction such as mounting filesystems, opening files, or clicking links is needed.\nS:U - Impact is kernel net_device refcount corruption/UAF within the host kernel security authority; it does not cross VM, IOMMU, or sandbox boundaries (standard kernel privilege escalation, not escape).\nC:H - Use-after-free of a net_device after refcount underflow (e.g., usage count=-2) exposes freed netdev/slab memory; per kernel UAF guidance this provides a high-impact arbitrary-read primitive via heap grooming.\nI:H - Corrupting freed net_device structures and reference counts is classic heap UAF that can be shaped into arbitrary kernel writes and control-flow hijack for code execution, per kernel memory-corruption guidance.\nA:H - Refcount imbalance causes unregister_netdevice to hang (usage count=-2), kernel oops/panic during tunnel teardown, and reliable denial of service on IPsec gateways even before full exploitation."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:44:29.613Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/63a30015199912bd5055bead8001b1ae68a67cdb"
        },
        {
          "url": "https://git.kernel.org/stable/c/8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff"
        }
      ],
      "title": "xfrm: Fix dev use-after-free in xfrm async resumption",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-72463",
    "datePublished": "2026-08-15T05:57:07.413Z",
    "dateReserved": "2026-08-09T03:40:39.933Z",
    "dateUpdated": "2026-08-17T05:44:29.613Z",
    "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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

FKIE_CVE-2026-72463

CVE-2026-72463 (GCVE-0-2026-72463)

Tags

Sightings

Nomenclature