Vulnerability-Lookup

GHSA-PCV5-GX25-24WJ

Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-17 06:33

Details

In the Linux kernel, the following vulnerability has been resolved:

gue: validate REMCSUM private option length

GUE private flags can indicate that remote checksum offload metadata is present. The private flags field itself is accounted for by guehdr_flags_len(), but guehdr_priv_flags_len() currently returns 0 even when GUE_PFLAG_REMCSUM is set.

This lets a packet with only the private flags field pass validate_gue_flags(), after which gue_remcsum() and gue_gro_remcsum() read the missing REMCSUM start/offset fields from the following bytes.

Account for GUE_PLEN_REMCSUM when GUE_PFLAG_REMCSUM is present so that malformed packets are rejected during option validation.

Severity

9.8 (Critical)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-72351"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-15T06:22:08Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ngue: validate REMCSUM private option length\n\nGUE private flags can indicate that remote checksum offload metadata is\npresent. The private flags field itself is accounted for by\nguehdr_flags_len(), but guehdr_priv_flags_len() currently returns 0 even\nwhen GUE_PFLAG_REMCSUM is set.\n\nThis lets a packet with only the private flags field pass\nvalidate_gue_flags(), after which gue_remcsum() and gue_gro_remcsum()\nread the missing REMCSUM start/offset fields from the following bytes.\n\nAccount for GUE_PLEN_REMCSUM when GUE_PFLAG_REMCSUM is present so that\nmalformed packets are rejected during option validation.",
  "id": "GHSA-pcv5-gx25-24wj",
  "modified": "2026-08-17T06:33:24Z",
  "published": "2026-08-15T06:32:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72351"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/158b9995d3c87f3b93f5c22df54a12e12a3438b3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2a99224c120823987e4d829726f4ecb33e03fc1e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2c4de9988e9ddc760b750d6b6e701c35ff60ad14"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4a4a1d41c6e901e773bcf795f562a47fa71f692a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/61e78679c7c9ca685bff58e4b6348304dc60aafd"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7c6876ec1b227261b51803f784c7be1b2242a1a0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d335dcc6f521571d57117b8deeebc940836e5450"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f618cbe9b24cd0202004d2db781d5f80ab77037f"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-72351 (GCVE-0-2026-72351)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:55 – Updated: 2026-08-17 05:43

Title

gue: validate REMCSUM private option length

Summary

In the Linux kernel, the following vulnerability has been resolved: gue: validate REMCSUM private option length GUE private flags can indicate that remote checksum offload metadata is present. The private flags field itself is accounted for by guehdr_flags_len(), but guehdr_priv_flags_len() currently returns 0 even when GUE_PFLAG_REMCSUM is set. This lets a packet with only the private flags field pass validate_gue_flags(), after which gue_remcsum() and gue_gro_remcsum() read the missing REMCSUM start/offset fields from the following bytes. Account for GUE_PLEN_REMCSUM when GUE_PFLAG_REMCSUM is present so that malformed packets are rejected during option validation.

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

8 references

URL	Tags
https://git.kernel.org/stable/c/158b9995d3c87f3b9…
https://git.kernel.org/stable/c/7c6876ec1b227261b…
https://git.kernel.org/stable/c/2c4de9988e9ddc760…
https://git.kernel.org/stable/c/2a99224c120823987…
https://git.kernel.org/stable/c/61e78679c7c9ca685…
https://git.kernel.org/stable/c/4a4a1d41c6e901e77…
https://git.kernel.org/stable/c/f618cbe9b24cd0202…
https://git.kernel.org/stable/c/d335dcc6f521571d5…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < 158b9995d3c87f3b93f5c22df54a12e12a3438b3 (git) Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < 7c6876ec1b227261b51803f784c7be1b2242a1a0 (git) Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < 2c4de9988e9ddc760b750d6b6e701c35ff60ad14 (git) Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < 2a99224c120823987e4d829726f4ecb33e03fc1e (git) Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < 61e78679c7c9ca685bff58e4b6348304dc60aafd (git) Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < 4a4a1d41c6e901e773bcf795f562a47fa71f692a (git) Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < f618cbe9b24cd0202004d2db781d5f80ab77037f (git) Affected: c1aa8347e73e4092411fbd96cc59531fb7e76d04 , < d335dcc6f521571d57117b8deeebc940836e5450 (git)
Linux	Linux	Affected: 3.19 Unaffected: 0 , < 3.19 (semver) Unaffected: 5.10.261 , ≤ 5.10.* (semver) Unaffected: 5.15.212 , ≤ 5.15.* (semver) Unaffected: 6.1.178 , ≤ 6.1.* (semver) Unaffected: 6.6.145 , ≤ 6.6.* (semver) Unaffected: 6.12.97 , ≤ 6.12.* (semver) Unaffected: 6.18.40 , ≤ 6.18.* (semver) Unaffected: 7.1.5 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/net/gue.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
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              "status": "affected",
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              "versionType": "git"
            },
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              "version": "c1aa8347e73e4092411fbd96cc59531fb7e76d04",
              "versionType": "git"
            },
            {
              "lessThan": "2c4de9988e9ddc760b750d6b6e701c35ff60ad14",
              "status": "affected",
              "version": "c1aa8347e73e4092411fbd96cc59531fb7e76d04",
              "versionType": "git"
            },
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            },
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            {
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              "version": "3.19"
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              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
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            {
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              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
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              "versionType": "semver"
            },
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              "lessThanOrEqual": "6.18.*",
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              "versionType": "semver"
            },
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            },
            {
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              "status": "unaffected",
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                {
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                {
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                  "versionStartIncluding": "3.19",
                  "vulnerable": true
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ngue: validate REMCSUM private option length\n\nGUE private flags can indicate that remote checksum offload metadata is\npresent. The private flags field itself is accounted for by\nguehdr_flags_len(), but guehdr_priv_flags_len() currently returns 0 even\nwhen GUE_PFLAG_REMCSUM is set.\n\nThis lets a packet with only the private flags field pass\nvalidate_gue_flags(), after which gue_remcsum() and gue_gro_remcsum()\nread the missing REMCSUM start/offset fields from the following bytes.\n\nAccount for GUE_PLEN_REMCSUM when GUE_PFLAG_REMCSUM is present so that\nmalformed packets are rejected during option validation."
        }
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        {
          "url": "https://git.kernel.org/stable/c/d335dcc6f521571d57117b8deeebc940836e5450"
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    "cveId": "CVE-2026-72351",
    "datePublished": "2026-08-15T05:55:54.150Z",
    "dateReserved": "2026-08-09T03:40:39.921Z",
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    "state": "PUBLISHED"
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  "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.

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GHSA-PCV5-GX25-24WJ

CVE-2026-72351 (GCVE-0-2026-72351)

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Sightings

Nomenclature