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EUVD-2026-364742

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 08:33

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": "2026-10-02T08:33:50.877256+00:00",
  "id": "EUVD-2026-364742"
}

CVE-2026-31449 (GCVE-0-2026-31449)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:53 – Updated: 2026-09-08 08:47

Title

ext4: validate p_idx bounds in ext4_ext_correct_indexes

Summary

In the Linux kernel, the following vulnerability has been resolved: ext4: validate p_idx bounds in ext4_ext_correct_indexes ext4_ext_correct_indexes() walks up the extent tree correcting index entries when the first extent in a leaf is modified. Before accessing path[k].p_idx->ei_block, there is no validation that p_idx falls within the valid range of index entries for that level. If the on-disk extent header contains a corrupted or crafted eh_entries value, p_idx can point past the end of the allocated buffer, causing a slab-out-of-bounds read. Fix this by validating path[k].p_idx against EXT_LAST_INDEX() at both access sites: before the while loop and inside it. Return -EFSCORRUPTED if the index pointer is out of range, consistent with how other bounds violations are handled in the ext4 extent tree code.

Severity

7.8 (High)


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

Assigner

Linux mitre root Scorecard

References

9 references

URL	Tags
https://git.kernel.org/stable/c/39d6e2b67651614ba…
https://git.kernel.org/stable/c/c5839b34704c9c2f4…
https://git.kernel.org/stable/c/10242e640b36b91ad…
https://git.kernel.org/stable/c/4d08401aa13f15312…
https://git.kernel.org/stable/c/407c944f217c17d43…
https://git.kernel.org/stable/c/93f2e975ed658ce09…
https://git.kernel.org/stable/c/01bf1e0b997d82c0e…
https://git.kernel.org/stable/c/2acb5c12ebd860f30…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

5 products

Vendor	Product	Version
Linux	Linux	Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 39d6e2b67651614bac0dc6592fa9836321910067 (git) Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < c5839b34704c9c2f47f079451bdbb22de0da1ed1 (git) Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 10242e640b36b91ad03d25f3dc77854bbdff8358 (git) Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 4d08401aa13f1531216f1a7ae281ca4806e90a5c (git) Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 407c944f217c17d4343148011acafebc604d55e1 (git) Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 93f2e975ed658ce09db4d4c2877ca2c06540df83 (git) Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 01bf1e0b997d82c0e353b51ed74ef99698043c33 (git) Affected: a86c61812637c7dd0c57e29880cffd477b62f2e7 , < 2acb5c12ebd860f30e4faf67e6cc8c44ddfe5fe8 (git)
Linux	Linux	Affected: 2.6.19 Unaffected: 0 , < 2.6.19 (semver) Unaffected: 5.10.259 , ≤ 5.10.* (semver) Unaffected: 5.15.210 , ≤ 5.15.* (semver) Unaffected: 6.1.175 , ≤ 6.1.* (semver) Unaffected: 6.6.140 , ≤ 6.6.* (semver) Unaffected: 6.12.80 , ≤ 6.12.* (semver) Unaffected: 6.18.21 , ≤ 6.18.* (semver) Unaffected: 6.19.11 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "affected": [
          {
            "defaultStatus": "unknown",
            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
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            "defaultStatus": "unknown",
            "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
            "vendor": "Siemens",
            "versions": [
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                "lessThan": "*",
                "status": "affected",
                "version": "V3.1.6",
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              }
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-08T08:47:15.427Z",
          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
        },
        "references": [
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
          }
        ],
        "x_adpType": "supplier"
      }
    ],
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          "product": "Linux",
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          "versions": [
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              "status": "affected",
              "version": "a86c61812637c7dd0c57e29880cffd477b62f2e7",
              "versionType": "git"
            },
            {
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              "status": "affected",
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              "versionType": "git"
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            {
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              "status": "affected",
              "version": "a86c61812637c7dd0c57e29880cffd477b62f2e7",
              "versionType": "git"
            },
            {
              "lessThan": "4d08401aa13f1531216f1a7ae281ca4806e90a5c",
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            {
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              "version": "0",
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            },
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              "lessThanOrEqual": "5.10.*",
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            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.210",
              "versionType": "semver"
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              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.175",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.140",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.80",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.21",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
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            }
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          "url": "https://git.kernel.org/stable/c/2acb5c12ebd860f30e4faf67e6cc8c44ddfe5fe8"
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31449",
    "datePublished": "2026-04-22T13:53:44.777Z",
    "dateReserved": "2026-03-09T15:48:24.091Z",
    "dateUpdated": "2026-09-08T08:47:15.427Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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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-2026-364742

CVE-2026-31449 (GCVE-0-2026-31449)

Tags

Sightings

Nomenclature

Related by attack behaviour