Vulnerability-Lookup

GHSA-PQHV-WX6P-7GP4

Vulnerability from github – Published: 2026-10-28 12:31 – Updated: 2026-10-28 12:31

Details

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

ring-buffer: Fix the sub-buffer array base in rb_meta_subbuf_idx()

On a persistent ring buffer, rb_meta_subbuf_idx() can return an index one sub-buffer too high. rb_setup_ids_meta_page() then fills subbuf_ids[] shifted by one and leaves subbuf_ids[0] NULL, which __rb_map_vma() dereferences when userspace maps trace_pipe_raw. rb_update_meta_reader() writes two such indices into meta->buffers[], which rb_cpu_meta_valid() would reject on the next boot, discarding the previous boot's trace.

A CPU's sub-buffer array starts after its meta header and the nr_subbufs integers that follow, aligned up to a sub-buffer. rb_meta_subbuf_idx() inverts that calculation but skips only the integers, not the header, so its base is one sub-buffer low whenever the omitted header size crosses the alignment boundary.

Invert the calculation with rb_subbufs_from_meta() rather than repeating it. rb_range_buffer() maps an index back to an address through the same helper, so the two directions can no longer disagree.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-99159"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-28T11:17:36Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix the sub-buffer array base in rb_meta_subbuf_idx()\n\nOn a persistent ring buffer, rb_meta_subbuf_idx() can return an index one\nsub-buffer too high.  rb_setup_ids_meta_page() then fills subbuf_ids[]\nshifted by one and leaves subbuf_ids[0] NULL, which __rb_map_vma()\ndereferences when userspace maps trace_pipe_raw.  rb_update_meta_reader()\nwrites two such indices into meta-\u003ebuffers[], which rb_cpu_meta_valid()\nwould reject on the next boot, discarding the previous boot\u0027s trace.\n\nA CPU\u0027s sub-buffer array starts after its meta header and the nr_subbufs\nintegers that follow, aligned up to a sub-buffer.  rb_meta_subbuf_idx()\ninverts that calculation but skips only the integers, not the header, so\nits base is one sub-buffer low whenever the omitted header size crosses\nthe alignment boundary.\n\nInvert the calculation with rb_subbufs_from_meta() rather than repeating\nit.  rb_range_buffer() maps an index back to an address through the same\nhelper, so the two directions can no longer disagree.",
  "id": "GHSA-pqhv-wx6p-7gp4",
  "modified": "2026-10-28T12:31:06Z",
  "published": "2026-10-28T12:31:06Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-99159"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/25132363c723afc39aace8b098f547ab4a0ea759"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2f1248b728b56d583ea454fedf239550c49f7b18"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7469b3585ef5f65840d467d2caa811a9098c84b9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-99159 (GCVE-0-2026-99159)

Vulnerability from cvelistv5 – Published: 2026-10-28 10:35 – Updated: 2026-10-28 10:35

Title

ring-buffer: Fix the sub-buffer array base in rb_meta_subbuf_idx()

Summary

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Fix the sub-buffer array base in rb_meta_subbuf_idx() On a persistent ring buffer, rb_meta_subbuf_idx() can return an index one sub-buffer too high. rb_setup_ids_meta_page() then fills subbuf_ids[] shifted by one and leaves subbuf_ids[0] NULL, which __rb_map_vma() dereferences when userspace maps trace_pipe_raw. rb_update_meta_reader() writes two such indices into meta->buffers[], which rb_cpu_meta_valid() would reject on the next boot, discarding the previous boot's trace. A CPU's sub-buffer array starts after its meta header and the nr_subbufs integers that follow, aligned up to a sub-buffer. rb_meta_subbuf_idx() inverts that calculation but skips only the integers, not the header, so its base is one sub-buffer low whenever the omitted header size crosses the alignment boundary. Invert the calculation with rb_subbufs_from_meta() rather than repeating it. rb_range_buffer() maps an index back to an address through the same helper, so the two directions can no longer disagree.

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7033 records in the last 180 days details

References

3 references

URL	Tags
https://git.kernel.org/stable/c/2f1248b728b56d583…
https://git.kernel.org/stable/c/7469b3585ef5f6584…
https://git.kernel.org/stable/c/25132363c723afc39…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: b14d032973d4e6c36e025e96ea3437de53d072d9 , < 2f1248b728b56d583ea454fedf239550c49f7b18 (git) Affected: b14d032973d4e6c36e025e96ea3437de53d072d9 , < 7469b3585ef5f65840d467d2caa811a9098c84b9 (git) Affected: b14d032973d4e6c36e025e96ea3437de53d072d9 , < 25132363c723afc39aace8b098f547ab4a0ea759 (git)
Linux	Linux	Affected: 6.12 Unaffected: 0 , < 6.12 (semver) Unaffected: 6.18.59 , ≤ 6.18.* (semver) Unaffected: 7.2.13 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/trace/ring_buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2f1248b728b56d583ea454fedf239550c49f7b18",
              "status": "affected",
              "version": "b14d032973d4e6c36e025e96ea3437de53d072d9",
              "versionType": "git"
            },
            {
              "lessThan": "7469b3585ef5f65840d467d2caa811a9098c84b9",
              "status": "affected",
              "version": "b14d032973d4e6c36e025e96ea3437de53d072d9",
              "versionType": "git"
            },
            {
              "lessThan": "25132363c723afc39aace8b098f547ab4a0ea759",
              "status": "affected",
              "version": "b14d032973d4e6c36e025e96ea3437de53d072d9",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/trace/ring_buffer.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.12"
            },
            {
              "lessThan": "6.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.59",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.59",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.13",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix the sub-buffer array base in rb_meta_subbuf_idx()\n\nOn a persistent ring buffer, rb_meta_subbuf_idx() can return an index one\nsub-buffer too high.  rb_setup_ids_meta_page() then fills subbuf_ids[]\nshifted by one and leaves subbuf_ids[0] NULL, which __rb_map_vma()\ndereferences when userspace maps trace_pipe_raw.  rb_update_meta_reader()\nwrites two such indices into meta-\u003ebuffers[], which rb_cpu_meta_valid()\nwould reject on the next boot, discarding the previous boot\u0027s trace.\n\nA CPU\u0027s sub-buffer array starts after its meta header and the nr_subbufs\nintegers that follow, aligned up to a sub-buffer.  rb_meta_subbuf_idx()\ninverts that calculation but skips only the integers, not the header, so\nits base is one sub-buffer low whenever the omitted header size crosses\nthe alignment boundary.\n\nInvert the calculation with rb_subbufs_from_meta() rather than repeating\nit.  rb_range_buffer() maps an index back to an address through the same\nhelper, so the two directions can no longer disagree."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-28T10:35:12.520Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2f1248b728b56d583ea454fedf239550c49f7b18"
        },
        {
          "url": "https://git.kernel.org/stable/c/7469b3585ef5f65840d467d2caa811a9098c84b9"
        },
        {
          "url": "https://git.kernel.org/stable/c/25132363c723afc39aace8b098f547ab4a0ea759"
        }
      ],
      "title": "ring-buffer: Fix the sub-buffer array base in rb_meta_subbuf_idx()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-99159",
    "datePublished": "2026-10-28T10:35:12.520Z",
    "dateReserved": "2026-09-25T10:25:14.397Z",
    "dateUpdated": "2026-10-28T10:35:12.520Z",
    "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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted