Vulnerability-Lookup

GHSA-6JQ9-9F7W-H7MC

Vulnerability from github – Published: 2026-08-20 12:31 – Updated: 2026-08-20 12:31

Details

A flaw was found in libvirt. An unprivileged local user could exploit an integer overflow vulnerability in the NodeGetFreePages RPC handler. This flaw allows crafted values to bypass a size check, leading to an undersized memory buffer. Subsequently, real NUMA node data can overwrite this buffer. This heap buffer overflow can corrupt the root libvirt daemon's memory, potentially leading to a denial of service or local privilege escalation.

Severity

7.8 (High)


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

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  "affected": [],
  "aliases": [
    "CVE-2026-18917"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-190"
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-20T10:16:40Z",
    "severity": "HIGH"
  },
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  "id": "GHSA-6jq9-9f7w-h7mc",
  "modified": "2026-08-20T12:31:21Z",
  "published": "2026-08-20T12:31:21Z",
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    },
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    },
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      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-18917 (GCVE-0-2026-18917)

Vulnerability from cvelistv5 – Published: 2026-08-20 09:54 – Updated: 2026-08-20 15:36

Title

Libvirt: integer overflow in nodegetfreepages rpc handler leading to heap buffer overflow

Summary

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/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 2026-08-20 15:33 UTC

CWE

CWE-190 - Integer Overflow or Wraparound

Assigner

redhat redhat root

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-18917	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2520161	issue-trackingx_refsource_REDHAT

Impacted products

6 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9
Red Hat	Red Hat Enterprise Linux for NVIDIA 26	cpe:/a:redhat:enterprise_linux_nvidia:

Date Public

2025-08-12 00:00

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JSON

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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.

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-6JQ9-9F7W-H7MC

CVE-2026-18917 (GCVE-0-2026-18917)

Tags

Sightings

Nomenclature