Vulnerability-Lookup

GHSA-7M85-FGV2-GV39

Vulnerability from github – Published: 2026-08-19 06:31 – Updated: 2026-08-19 18:32

Details

An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges.

Severity

8.4 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-49428"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-915"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-19T06:17:42Z",
    "severity": "HIGH"
  },
  "details": "Certain system calls, such open(2) with the O_TRUNC flag set, and fspacectl(2), could incorrectly free memory in largepage objects.  These operations are not permitted on largepage objects, but the implementation did not verify this.\n\nAn unprivileged local user can abuse the bug to access freed kernel memory.  This can be exploited to escalate privileges.",
  "id": "GHSA-7m85-fgv2-gv39",
  "modified": "2026-08-19T18:32:45Z",
  "published": "2026-08-19T06:31:18Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-49428"
    },
    {
      "type": "WEB",
      "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:44.posixshm.asc"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-49428 (GCVE-0-2026-49428)

Vulnerability from cvelistv5 – Published: 2026-08-19 05:57 – Updated: 2026-08-20 03:55

Title

posixshm: system calls can incorrectly free memory of largepage objects

Summary

Certain system calls, such open(2) with the O_TRUNC flag set, and fspacectl(2), could incorrectly free memory in largepage objects. These operations are not permitted on largepage objects, but the implementation did not verify this. An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges.

Severity

8.4 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-19 00:00 UTC

CWE

CWE-915 - Improperly Controlled Modification of Dynamically-Determined Object Attributes

Assigner

freebsd mitre root

References

1 reference

URL	Tags
https://security.freebsd.org/advisories/FreeBSD-S…	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
FreeBSD	FreeBSD	Affected: 15.1-RELEASE , < p1 (release) Affected: 15.0-RELEASE , < p11 (release) Affected: 14.4-RELEASE , < p7 (release) Affected: 14.3-RELEASE , < p16 (release)

Date Public

2026-06-30 20:00

Credits

Chris Jarrett-Davies of the OpenAI Codex Security Team

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JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 8.4,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-49428",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-19T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-20T03:55:45.923Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "modules": [
            "posixshm"
          ],
          "product": "FreeBSD",
          "vendor": "FreeBSD",
          "versions": [
            {
              "lessThan": "p1",
              "status": "affected",
              "version": "15.1-RELEASE",
              "versionType": "release"
            },
            {
              "lessThan": "p11",
              "status": "affected",
              "version": "15.0-RELEASE",
              "versionType": "release"
            },
            {
              "lessThan": "p7",
              "status": "affected",
              "version": "14.4-RELEASE",
              "versionType": "release"
            },
            {
              "lessThan": "p16",
              "status": "affected",
              "version": "14.3-RELEASE",
              "versionType": "release"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Chris Jarrett-Davies of the OpenAI Codex Security Team"
        }
      ],
      "datePublic": "2026-06-30T20:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Certain system calls, such open(2) with the O_TRUNC flag set, and fspacectl(2), could incorrectly free memory in largepage objects.  These operations are not permitted on largepage objects, but the implementation did not verify this.\n\nAn unprivileged local user can abuse the bug to access freed kernel memory.  This can be exploited to escalate privileges."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-915",
              "description": "CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-19T05:57:04.674Z",
        "orgId": "63664ac6-956c-4cba-a5d0-f46076e16109",
        "shortName": "freebsd"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:44.posixshm.asc"
        }
      ],
      "title": "posixshm: system calls can incorrectly free memory of largepage objects",
      "x_generator": {
        "engine": "cvelib 1.8.0"
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  "cveMetadata": {
    "assignerOrgId": "63664ac6-956c-4cba-a5d0-f46076e16109",
    "assignerShortName": "freebsd",
    "cveId": "CVE-2026-49428",
    "datePublished": "2026-08-19T05:57:04.674Z",
    "dateReserved": "2026-05-29T20:24:28.616Z",
    "dateUpdated": "2026-08-20T03:55:45.923Z",
    "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

GHSA-7M85-FGV2-GV39

CVE-2026-49428 (GCVE-0-2026-49428)

Tags

Sightings

Nomenclature