Vulnerability-Lookup

GHSA-9GX7-G5HV-XJJJ

Vulnerability from github – Published: 2026-05-18 15:30 – Updated: 2026-05-18 15:30

Details

A flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This could lead to unstable packet ordering or undefined behavior, resulting in a denial of service.

Severity ?

7.5 (High)


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

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  "affected": [],
  "aliases": [
    "CVE-2026-42009"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-475"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-18T13:16:32Z",
    "severity": "HIGH"
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  "id": "GHSA-9gx7-g5hv-xjjj",
  "modified": "2026-05-18T15:30:37Z",
  "published": "2026-05-18T15:30:37Z",
  "references": [
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42009"
    },
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      "url": "https://access.redhat.com/security/cve/CVE-2026-42009"
    },
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      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467279"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
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      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-42009 (GCVE-0-2026-42009)

Vulnerability from cvelistv5 – Published: 2026-05-18 12:44 – Updated: 2026-05-18 19:05

Title

Gnutls: gnutls: denial of service via dtls packet reordering vulnerability

Summary

Severity ?

7.5 (High)


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

CWE

CWE-475 - Undefined Behavior for Input to API

Assigner

redhat

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-42009	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2467279	issue-trackingx_refsource_REDHAT

Impacted products

7 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 Hardened Images	cpe:/a:redhat:hummingbird:1
Red Hat	Red Hat OpenShift Container Platform 4	cpe:/a:redhat:openshift:4

Date Public ?

2026-04-29 00:00

Credits

Red Hat would like to thank Joshua Rogers (AISLE Research Team) for reporting this issue.

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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.

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GHSA-9GX7-G5HV-XJJJ

CVE-2026-42009 (GCVE-0-2026-42009)

Tags

Sightings

Nomenclature