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EUVD-2026-348292

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 08:18

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

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{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T08:18:52.354357+00:00",
  "id": "EUVD-2026-348292"
}

CVE-2026-63912 (GCVE-0-2026-63912)

Vulnerability from cvelistv5 – Published: 2026-07-19 14:55 – Updated: 2026-08-05 12:37

Title

xfrm: esp: restore combined single-frag length gate

Summary

In the Linux kernel, the following vulnerability has been resolved: xfrm: esp: restore combined single-frag length gate The ESP out-of-place fast path appends the trailer in esp_output_head() before esp_output_tail() allocates the destination page frag. The head-side gate currently checks skb->data_len and tailen separately, but the tail code allocates a single destination frag from the combined post-trailer skb->data_len. Reject the page-frag fast path when the combined aligned length exceeds a page. Otherwise skb_page_frag_refill() may fall back to a single page while the destination sg still spans the combined skb->data_len. Restore this combined-length page gate for both IPv4 and IPv6.

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 Scorecard

References

8 references

URL	Tags
https://git.kernel.org/stable/c/566295735530ee513…
https://git.kernel.org/stable/c/5d7ab86e2b6bc2305…
https://git.kernel.org/stable/c/36519e3d941fc99d3…
https://git.kernel.org/stable/c/322e48187e0245ab2…
https://git.kernel.org/stable/c/b84091ceddc9f1332…
https://git.kernel.org/stable/c/c093468aea8277f77…
https://git.kernel.org/stable/c/65f3b3fc2347b89fe…
https://git.kernel.org/stable/c/dfa0d7b0ff1eb6b2c…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: c075c3ea031757f8ea2d34567565b61a868c08d5 , < 566295735530ee513326049b0540f32ec050bf2e (git) Affected: a583f2f3c8788bffd7fd7baeb76bd6d80543d7ea , < 5d7ab86e2b6bc23054616bf6ac562013bf60af8c (git) Affected: 5bd8baab087dff657e05387aee802e70304cc813 , < 36519e3d941fc99d3b52c134dbaf311f987a4708 (git) Affected: 5bd8baab087dff657e05387aee802e70304cc813 , < 322e48187e0245ab2fff6fec2220b0cae677dbec (git) Affected: 5bd8baab087dff657e05387aee802e70304cc813 , < b84091ceddc9f133229dceab3ccc930bf27f9cba (git) Affected: 5bd8baab087dff657e05387aee802e70304cc813 , < c093468aea8277f77272a4f199b2e15e19cabb59 (git) Affected: 5bd8baab087dff657e05387aee802e70304cc813 , < 65f3b3fc2347b89fe21db1e92c7681368415f095 (git) Affected: 5bd8baab087dff657e05387aee802e70304cc813 , < dfa0d7b0ff1eb6b2c416b8fdb9b4f2cefba57a40 (git) Affected: 2c66b0c95bb0aa7652ba1eba293d0d5993b35a38 (git) Affected: ef6f83df1209a7d9bd1c605a62457d4c00f9179e (git) Affected: 3defefd22ad5fbbe639b6157fb7e6311b2bf333d (git) Affected: b657030870bb5351c5b1e84d4e9f186da6ca0496 (git) Affected: 5.10.113 , < 5.10.259 (semver) Affected: 5.15.36 , < 5.15.210 (semver) Affected: 4.14.288 , < 4.15 (semver) Affected: 4.19.252 , < 4.20 (semver) Affected: 5.4.205 , < 5.5 (semver) Affected: 5.17.5 , < 5.18 (semver)
Linux	Linux	Affected: 5.18 Unaffected: 0 , < 5.18 (semver) Unaffected: 5.10.259 , ≤ 5.10.* (semver) Unaffected: 5.15.210 , ≤ 5.15.* (semver) Unaffected: 6.1.176 , ≤ 6.1.* (semver) Unaffected: 6.6.143 , ≤ 6.6.* (semver) Unaffected: 6.12.93 , ≤ 6.12.* (semver) Unaffected: 6.18.35 , ≤ 6.18.* (semver) Unaffected: 7.0.12 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix)

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JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/esp4.c",
            "net/ipv6/esp6.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "566295735530ee513326049b0540f32ec050bf2e",
              "status": "affected",
              "version": "c075c3ea031757f8ea2d34567565b61a868c08d5",
              "versionType": "git"
            },
            {
              "lessThan": "5d7ab86e2b6bc23054616bf6ac562013bf60af8c",
              "status": "affected",
              "version": "a583f2f3c8788bffd7fd7baeb76bd6d80543d7ea",
              "versionType": "git"
            },
            {
              "lessThan": "36519e3d941fc99d3b52c134dbaf311f987a4708",
              "status": "affected",
              "version": "5bd8baab087dff657e05387aee802e70304cc813",
              "versionType": "git"
            },
            {
              "lessThan": "322e48187e0245ab2fff6fec2220b0cae677dbec",
              "status": "affected",
              "version": "5bd8baab087dff657e05387aee802e70304cc813",
              "versionType": "git"
            },
            {
              "lessThan": "b84091ceddc9f133229dceab3ccc930bf27f9cba",
              "status": "affected",
              "version": "5bd8baab087dff657e05387aee802e70304cc813",
              "versionType": "git"
            },
            {
              "lessThan": "c093468aea8277f77272a4f199b2e15e19cabb59",
              "status": "affected",
              "version": "5bd8baab087dff657e05387aee802e70304cc813",
              "versionType": "git"
            },
            {
              "lessThan": "65f3b3fc2347b89fe21db1e92c7681368415f095",
              "status": "affected",
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              "versionType": "git"
            },
            {
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              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "2c66b0c95bb0aa7652ba1eba293d0d5993b35a38",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "ef6f83df1209a7d9bd1c605a62457d4c00f9179e",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3defefd22ad5fbbe639b6157fb7e6311b2bf333d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b657030870bb5351c5b1e84d4e9f186da6ca0496",
              "versionType": "git"
            },
            {
              "lessThan": "5.10.259",
              "status": "affected",
              "version": "5.10.113",
              "versionType": "semver"
            },
            {
              "lessThan": "5.15.210",
              "status": "affected",
              "version": "5.15.36",
              "versionType": "semver"
            },
            {
              "lessThan": "4.15",
              "status": "affected",
              "version": "4.14.288",
              "versionType": "semver"
            },
            {
              "lessThan": "4.20",
              "status": "affected",
              "version": "4.19.252",
              "versionType": "semver"
            },
            {
              "lessThan": "5.5",
              "status": "affected",
              "version": "5.4.205",
              "versionType": "semver"
            },
            {
              "lessThan": "5.18",
              "status": "affected",
              "version": "5.17.5",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/esp4.c",
            "net/ipv6/esp6.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.18"
            },
            {
              "lessThan": "5.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.259",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.210",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.176",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.143",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.93",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.35",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.0.*",
              "status": "unaffected",
              "version": "7.0.12",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.259",
                  "versionStartIncluding": "5.10.113",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.210",
                  "versionStartIncluding": "5.15.36",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.176",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.143",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
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                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.93",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.35",
                  "versionStartIncluding": "5.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "5.18",
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                },
                {
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                  "versionEndExcluding": "7.1",
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                },
                {
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                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.19.252",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.4.205",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.17.5",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: esp: restore combined single-frag length gate\n\nThe ESP out-of-place fast path appends the trailer in esp_output_head()\nbefore esp_output_tail() allocates the destination page frag. The\nhead-side gate currently checks skb-\u003edata_len and tailen separately, but\nthe tail code allocates a single destination frag from the combined\npost-trailer skb-\u003edata_len.\n\nReject the page-frag fast path when the combined aligned length exceeds a\npage. Otherwise skb_page_frag_refill() may fall back to a single page while\nthe destination sg still spans the combined skb-\u003edata_len.\n\nRestore this combined-length page gate for both IPv4 and IPv6."
        }
      ],
      "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 bug is in the ESP outbound encryption path reached when IPsec-protected traffic is sent through xfrm (e.g., from an internet-facing VPN/tunnel gateway encrypting responses or forwarded flows to a remote peer). A network peer can influence outbound skb fragment sizes to hit the vulnerable fast path without local shell access.\nAC:L - An attacker can reliably craft payload sizes so ALIGN(skb-\u003edata_len) and ALIGN(tailen) each pass the broken per-field PAGE_SIZE gate while their combined aligned length exceeds PAGE_SIZE, repeatedly probing until the out-of-place page-frag path is taken.\nPR:N - Exploitation does not require configuring xfrm or host admin rights; it only needs the target to already run ESP and the attacker to send traffic that is encrypted on output (e.g., as a remote VPN/site-to-site peer), which is network-layer access rather than local OS privilege.\nUI:N - Triggering the vulnerable ESP output path requires only attacker-controlled network traffic and does not depend on any victim user action such as mounting a filesystem or opening a file.\nS:U - Impact is confined to kernel memory corruption and privilege escalation within the same kernel security authority, not a cross-boundary escape such as guest-to-host VM breakout or IOMMU bypass.\nC:H - The flaw is a heap out-of-bounds write during AEAD encryption over an undersized page frag; such memory corruption can expose adjacent kernel objects and be leveraged for arbitrary memory disclosure, not merely a bounded leak.\nI:H - Writing past the allocated page-frag buffer corrupts adjacent heap memory and can be developed into arbitrary write or control-flow hijack primitives, matching kernel guidance for out-of-bounds writes.\nA:H - Corrupting kernel heap memory during crypto output can cause immediate kernel oops/panic or persistent instability, and repeated triggering can deny service on VPN gateways and other IPsec endpoints."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:37:06.161Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/566295735530ee513326049b0540f32ec050bf2e"
        },
        {
          "url": "https://git.kernel.org/stable/c/5d7ab86e2b6bc23054616bf6ac562013bf60af8c"
        },
        {
          "url": "https://git.kernel.org/stable/c/36519e3d941fc99d3b52c134dbaf311f987a4708"
        },
        {
          "url": "https://git.kernel.org/stable/c/322e48187e0245ab2fff6fec2220b0cae677dbec"
        },
        {
          "url": "https://git.kernel.org/stable/c/b84091ceddc9f133229dceab3ccc930bf27f9cba"
        },
        {
          "url": "https://git.kernel.org/stable/c/c093468aea8277f77272a4f199b2e15e19cabb59"
        },
        {
          "url": "https://git.kernel.org/stable/c/65f3b3fc2347b89fe21db1e92c7681368415f095"
        },
        {
          "url": "https://git.kernel.org/stable/c/dfa0d7b0ff1eb6b2c416b8fdb9b4f2cefba57a40"
        }
      ],
      "title": "xfrm: esp: restore combined single-frag length gate",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-63912",
    "datePublished": "2026-07-19T14:55:17.188Z",
    "dateReserved": "2026-07-19T07:54:57.020Z",
    "dateUpdated": "2026-08-05T12:37:06.161Z",
    "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.
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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.

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.
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EUVD-2026-348292

CVE-2026-63912 (GCVE-0-2026-63912)

Tags

Sightings

Nomenclature

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