FKIE_CVE-2026-40211

Vulnerability from fkie_nvd - Published: 2026-06-25 13:16 - Updated: 2026-06-25 15:59
Severity
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
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.
References
security@open-xchange.comhttps://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo.powerdns.com/",
          "defaultStatus": "unaffected",
          "modules": [
            "DNS over HTTP3"
          ],
          "packageName": "dnsdist",
          "product": "DNSdist",
          "programFiles": [
            "dnsdist-crypto.cc"
          ],
          "repo": "https://github.com/PowerDNS/pdns",
          "vendor": "PowerDNS",
          "versions": [
            {
              "lessThan": "1.9.15",
              "status": "affected",
              "version": "1.9.0",
              "versionType": "semver"
            },
            {
              "lessThan": "2.0.7",
              "status": "affected",
              "version": "2.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "security@open-xchange.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-40211",
  "lastModified": "2026-06-25T15:59:47.100",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "security@open-xchange.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-40211",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-25T13:44:56.582604Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-25T13:16:39.717",
  "references": [
    {
      "source": "security@open-xchange.com",
      "url": "https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html"
    }
  ],
  "sourceIdentifier": "security@open-xchange.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}


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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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