Vulnerability-Lookup

CVE-2026-93009 (GCVE-0-2026-93009)

Vulnerability from cvelistv5 – Published: 2026-10-29 13:13 – Updated: 2026-10-29 13:13

Title

Dnsmasq: dnsmasq: heap out-of-bounds read in dhcpv6 option 39 fqdn decoder

Summary

A flaw was found in dnsmasq. The DHCPv6 client hostname parser can read one byte past the end of a crafted FQDN option because it checks the next label length before confirming the pointer is still inside the option. An attacker on the local network can trigger this with a single DHCPv6 packet. The extra byte is not returned to the client or logged, and no crash has been demonstrated.

Severity

4.3 (Medium)


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

CWE

CWE-125 - Out-of-bounds Read

Assigner

redhat CNA under the redhat root

CNA scorecard B 82/100 over 1063 records in the last 180 days details

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-93009	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2536083	issue-trackingx_refsource_REDHAT

Impacted products

9 products

Vendor	Product	Version
Red Hat	Red Hat Ceph Storage 9	cpe:/a:redhat:ceph_storage:9
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 OpenShift Container Platform 4	cpe:/a:redhat:openshift:4
Red Hat	Red Hat OpenStack Platform 13 (Queens)	cpe:/a:redhat:openstack:13
Red Hat	Red Hat OpenStack Platform 18.0	cpe:/a:redhat:openstack:18.0

Date Public

2026-10-28 09:30

Credits

Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue.

Show details on NVD website

JSON

To clipboard

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GHSA-6QRC-RPQW-59WP

Vulnerability from github – Published: 2026-10-29 15:30 – Updated: 2026-10-29 15:30

Details

Severity

4.3 (Medium)


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

Show details on source website

JSON

To clipboard

{
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    "CVE-2026-93009"
  ],
  "database_specific": {
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    ],
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    "github_reviewed_at": null,
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    "severity": "MODERATE"
  },
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  "id": "GHSA-6qrc-rpqw-59wp",
  "modified": "2026-10-29T15:30:54Z",
  "published": "2026-10-29T15:30:54Z",
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      "type": "CVSS_V3"
    }
  ]
}

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

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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.

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