CVE-2026-12523

{
  "id": "CVE-2026-12523",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-14T16:16:45.050",
  "lastModified": "2026-10-24T21:10:00.130",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Summary\n\n\n\nCloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion (i.e., memory) by means of specially crafted HTTP/3 frames.\n\n\n\n\nImpact\n\n\n\nHTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload whose length depends on the frame type. quiche was found to be vulnerable when parsing some frame types to pre-allocating memory based on the declared length. An attacker would not need to send the number of declared bytes to trigger this issue.\n\n\n\nIn addition, quiche was found to not apply QPACK decompression limits correctly. This could allow an attacker to send specially crafted HEADERS frames that would cause more memory commitment than otherwise advertised by MAX_FIELD_SECTION_SIZE (configured by set_max_field_section_size()).\n\n\n\n\n\n\nMitigation:\n\n  *  \n\nUsers are requested to upgrade to quiche 0.29.3 which is the earliest version containing the fix for this issue.\n\n\n\n\n\n\n\n\n\nCredits: Disclosed responsibly by Sébastien Féry"
    },
    {
      "lang": "es",
      "value": "Resumen\n\nSe descubrió que la capa HTTP/3 de Cloudflare quiche era vulnerable al agotamiento de recursos (es decir, memoria) por medio de tramas HTTP/3 especialmente diseñadas.\n\nImpacto\n\nHTTP/3 define múltiples tipos de tramas para soportar los intercambios de mensajes HTTP y la gestión de conexiones. Cada trama tiene una longitud y una carga útil cuya longitud depende del tipo de trama. Se descubrió que quiche era vulnerable al analizar algunos tipos de tramas a la preasignación de memoria basándose en la longitud declarada. Un atacante no necesitaría enviar el número de bytes declarados para activar este problema.\n\nAdemás, se descubrió que quiche no aplicaba los límites de descompresión QPACK correctamente. Esto podría permitir a un atacante enviar tramas HEADERS especialmente diseñadas que causarían un mayor compromiso de memoria de lo que se anunciaría de otro modo por MAX_FIELD_SECTION_SIZE (configurado por set_max_field_section_size()).\n\nMitigación:\n\n  *  Se solicita a los usuarios que actualicen a quiche 0.29.3, que es la versión más temprana que contiene la corrección para este problema.\n\nCréditos: Divulgado responsablemente por Sébastien Féry"
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Cloudflare",
          "product": "quiche",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0.1.0",
              "lessThan": "0.29.3",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-15T14:08:33.441723Z",
          "id": "CVE-2026-12523",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:cloudflare:quiche:*:*:*:*:*:rust:*:*",
              "versionStartIncluding": "0.1.0",
              "versionEndExcluding": "0.29.3",
              "matchCriteriaId": "61C1D9E8-B9EC-4441-A5A4-AD4413951600"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/cloudflare/quiche/security/advisories/GHSA-4fgf-9xrr-88gf",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    }
  ]
}