Vulnerability-Lookup

GHSA-8MQG-G8G6-FVW6

Vulnerability from github – Published: 2026-06-25 15:31 – Updated: 2026-06-25 15:31

Details

An attacker can send crafted DNS over HTTP/3 queries, triggering an exception that prevents some buffer from being freed right away. The buffer will be freed at the end of the QUIC connection, but on some setups it might be possible to open enough concurrent DoH3 streams to trigger an out-of-memory condition, resulting in a denial of service.

Severity

5.3 (Medium)


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

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  "affected": [],
  "aliases": [
    "CVE-2026-40211"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-25T13:16:39Z",
    "severity": "MODERATE"
  },
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  "id": "GHSA-8mqg-g8g6-fvw6",
  "modified": "2026-06-25T15:31:59Z",
  "published": "2026-06-25T15:31:59Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40211"
    },
    {
      "type": "WEB",
      "url": "https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html"
    }
  ],
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      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-40211 (GCVE-0-2026-40211)

Vulnerability from cvelistv5 – Published: 2026-06-25 12:23 – Updated: 2026-06-25 13:45

Title

Denial of service via crafted DoH3 queries

Summary

Severity

5.3 (Medium)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

Allocation of Resources Without Limits or Throttling
CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

References

1 reference

URL	Tags
https://www.dnsdist.org/security-advisories/power…

Impacted products

1 product

Vendor	Product	Version
PowerDNS	DNSdist	Affected: 1.9.0 , < 1.9.15 (semver) Affected: 2.0.0 , < 2.0.7 (semver)

Date Public

2026-06-24 22:00

Credits

Mehtab Zafar

Show details on NVD website

JSON

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                "timestamp": "2026-06-25T13:44:56.582604Z",
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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.

Action not permitted

GHSA-8MQG-G8G6-FVW6

CVE-2026-40211 (GCVE-0-2026-40211)

Tags

Sightings

Nomenclature