CVE-2026-10652

{
  "id": "CVE-2026-10652",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-30T17:16:20.040",
  "lastModified": "2026-10-25T21:10:00.770",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Zephyr's DNS resolver (subsys/net/lib/dns) parses resource records from DNS responses in dns_unpack_answer(), which validated only the fixed RR header (type, class, TTL, rdlength) and accepted any attacker-declared rdlength, including one extending past the end of the received datagram. The TXT and SRV consumers in dns_validate_record() (resolve.c) then read up to rdlength bytes (clamped only to a record-type maximum such as DNS_MAX_TEXT_SIZE, default 64, not to the packet) from the receive buffer via memcpy without their own bounds check, and pass the result to the application's resolve callback. A malicious or spoofed DNS server, an on-path attacker forging UDP DNS replies, or (with mDNS/LLMNR enabled) any LAN node can craft a truncated TXT or SRV response that causes an out-of-bounds read of adjacent receive-pool memory; the disclosed stale bytes (residual contents of prior DNS packets / uninitialized pool memory) are returned to the application as TXT/SRV record contents, an information leak, and may in some configurations cross the allocation boundary and fault, causing a denial of service. The read is bounded (~64 bytes for TXT, ~6 for SRV) and read-only (no write). The fix rejects any record whose declared rdata extends past dns_msg->msg_size at the single chokepoint in dns_unpack_answer(). Affected: v4.3.0 and v4.4.0."
    },
    {
      "lang": "es",
      "value": "El resolvedor DNS de Zephyr (subsys/net/lib/dns) analiza registros de recursos de respuestas DNS en dns_unpack_answer(), que validaba solo la cabecera RR fija (tipo, clase, TTL, rdlength) y aceptaba cualquier rdlength declarado por el atacante, incluyendo uno que se extendía más allá del final del datagrama recibido. Los consumidores TXT y SRV en dns_validate_record() (resolve.c) luego leen hasta rdlength bytes (limitado solo a un máximo de tipo de registro como DNS_MAX_TEXT_SIZE, predeterminado 64, no al paquete) del búfer de recepción a través de memcpy sin su propia comprobación de límites, y pasan el resultado a la devolución de llamada de resolución de la aplicación. Un servidor DNS malicioso o suplantado, un atacante en la ruta que falsifica respuestas DNS UDP, o (con mDNS/LLMNR habilitado) cualquier nodo de LAN puede crear una respuesta TXT o SRV truncada que causa una lectura fuera de límites de la memoria adyacente del grupo de recepción; los bytes obsoletos divulgados (contenido residual de paquetes DNS anteriores / memoria de grupo no inicializada) se devuelven a la aplicación como contenido de registro TXT/SRV, una fuga de información, y pueden, en algunas configuraciones, cruzar el límite de asignación y fallar, causando una denegación de servicio. La lectura está limitada (~64 bytes para TXT, ~6 para SRV) y es de solo lectura (sin escritura). La corrección rechaza cualquier registro cuyo rdata declarado se extiende más allá de dns_msg  ->  msg_size en el único punto de estrangulamiento en dns_unpack_answer(). Afectado: v4.3.0 y v4.4.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "zephyrproject",
          "product": "zephyr",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
          "packageName": "zephyr",
          "programFiles": [
            "subsys/net/lib/dns/dns_pack.c"
          ],
          "versions": [
            {
              "version": "4.3.0",
              "lessThan": "4.3.1",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "4.4.0",
              "lessThan": "4.4.1",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L",
          "baseScore": 4.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 2.5
      },
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H",
          "baseScore": 7.4,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 5.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-30T16:44:24.969113Z",
          "id": "CVE-2026-10652",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "4.3.0",
              "versionEndIncluding": "4.4.1",
              "matchCriteriaId": "AB673835-4CCD-49A7-9873-630B9EE2C814"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/commit/58b46c81c6796dac4dc7391f32ba006474f94dc8",
      "source": "[email protected]",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-3jxq-xx8g-q8j2",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Patch",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-3jxq-xx8g-q8j2",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Patch",
        "Vendor Advisory"
      ]
    }
  ]
}