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GHSA-33W3-5969-WXFC

Vulnerability from github – Published: 2026-08-10 15:33 – Updated: 2026-08-19 18:32

Details

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

libceph: reject zero bucket types in crush_decode

CRUSH bucket type 0 is reserved for devices. The mapper relies on that invariant and uses type 0 to identify leaf devices.

If crush_decode() accepts a bucket with type 0, a malformed CRUSH map can make the mapper treat a negative bucket ID as a device and pass it to is_out(), which then indexes the OSD weight array with a negative value.

Reject zero bucket types while decoding the CRUSH map so the invalid state never reaches the mapper.

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-2026-68154"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T13:20:01Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: reject zero bucket types in crush_decode\n\nCRUSH bucket type 0 is reserved for devices.  The mapper relies on\nthat invariant and uses type 0 to identify leaf devices.\n\nIf crush_decode() accepts a bucket with type 0, a malformed CRUSH map\ncan make the mapper treat a negative bucket ID as a device and pass it\nto is_out(), which then indexes the OSD weight array with a negative\nvalue.\n\nReject zero bucket types while decoding the CRUSH map so the invalid\nstate never reaches the mapper.",
  "id": "GHSA-33w3-5969-wxfc",
  "modified": "2026-08-19T18:32:07Z",
  "published": "2026-08-10T15:33:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68154"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/05f90284223381005d6bcddab3fda4a97f9c3401"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/146461f09565afe3665e65b0423d3d6b0fe806c5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3b2f1937f5fce8b7dd5432e7693e3cc8b5eece56"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/70998f91030ee083ecb336a1dff0701c20a38081"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/80fc40e11cda1b5d990a3f69c6efa344fb5cd987"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/826cd1de5802fd392922785f9b64d76e65d2a100"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/952ca5dc99913d169263f59fd689f586729a13c1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b8a9fb6bf806f9c4891e71ae1beab0c07c23a877"
    }
  ],
  "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-2026-68154 (GCVE-0-2026-68154)

Vulnerability from cvelistv5 – Published: 2026-08-10 11:59 – Updated: 2026-08-19 16:30

Title

libceph: reject zero bucket types in crush_decode

Summary

In the Linux kernel, the following vulnerability has been resolved: libceph: reject zero bucket types in crush_decode CRUSH bucket type 0 is reserved for devices. The mapper relies on that invariant and uses type 0 to identify leaf devices. If crush_decode() accepts a bucket with type 0, a malformed CRUSH map can make the mapper treat a negative bucket ID as a device and pass it to is_out(), which then indexes the OSD weight array with a negative value. Reject zero bucket types while decoding the CRUSH map so the invalid state never reaches the mapper.

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/952ca5dc99913d169…
https://git.kernel.org/stable/c/146461f09565afe36…
https://git.kernel.org/stable/c/80fc40e11cda1b5d9…
https://git.kernel.org/stable/c/b8a9fb6bf806f9c48…
https://git.kernel.org/stable/c/826cd1de5802fd392…
https://git.kernel.org/stable/c/3b2f1937f5fce8b7d…
https://git.kernel.org/stable/c/70998f91030ee083e…
https://git.kernel.org/stable/c/05f90284223381005…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < 952ca5dc99913d169263f59fd689f586729a13c1 (git) Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < 146461f09565afe3665e65b0423d3d6b0fe806c5 (git) Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < 80fc40e11cda1b5d990a3f69c6efa344fb5cd987 (git) Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < b8a9fb6bf806f9c4891e71ae1beab0c07c23a877 (git) Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < 826cd1de5802fd392922785f9b64d76e65d2a100 (git) Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < 3b2f1937f5fce8b7dd5432e7693e3cc8b5eece56 (git) Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < 70998f91030ee083ecb336a1dff0701c20a38081 (git) Affected: f24e9980eb860d8600cbe5ef3d2fd9295320d229 , < 05f90284223381005d6bcddab3fda4a97f9c3401 (git)
Linux	Linux	Affected: 2.6.34 Unaffected: 0 , < 2.6.34 (semver) Unaffected: 5.10.265 , ≤ 5.10.* (semver) Unaffected: 5.15.216 , ≤ 5.15.* (semver) Unaffected: 6.1.183 , ≤ 6.1.* (semver) Unaffected: 6.6.148 , ≤ 6.6.* (semver) Unaffected: 6.12.101 , ≤ 6.12.* (semver) Unaffected: 6.18.42 , ≤ 6.18.* (semver) Unaffected: 7.1.6 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ceph/osdmap.c"
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          "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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              "status": "unaffected",
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              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.216",
              "versionType": "semver"
            },
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              "status": "unaffected",
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: reject zero bucket types in crush_decode\n\nCRUSH bucket type 0 is reserved for devices.  The mapper relies on\nthat invariant and uses type 0 to identify leaf devices.\n\nIf crush_decode() accepts a bucket with type 0, a malformed CRUSH map\ncan make the mapper treat a negative bucket ID as a device and pass it\nto is_out(), which then indexes the OSD weight array with a negative\nvalue.\n\nReject zero bucket types while decoding the CRUSH map so the invalid\nstate never reaches the mapper."
        }
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            }
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        "dateUpdated": "2026-08-19T16:30:20.481Z",
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    "cveId": "CVE-2026-68154",
    "datePublished": "2026-08-10T11:59:20.250Z",
    "dateReserved": "2026-07-30T09:28:09.371Z",
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    "state": "PUBLISHED"
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}

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.

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-33W3-5969-WXFC

CVE-2026-68154 (GCVE-0-2026-68154)

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