CVE-2026-10634

{
  "id": "CVE-2026-10634",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-15T16:16:32.223",
  "lastModified": "2026-10-25T23:10:00.167",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Zephyr's native TCP stack iterates the global connection list in net_tcp_foreach() (subsys/net/ip/tcp.c) using the SYS_SLIST_FOR_EACH_CONTAINER_SAFE macro, which caches a pointer to the next list node. Prior to this fix the function released tcp_lock while invoking the per-connection callback and re-acquired it afterwards.\n\nDuring that window a concurrent tcp_conn_release(), running on the dedicated TCP work-queue thread when a connection's reference count drops to zero (e.g. a remote peer closing or resetting the connection), can remove and k_mem_slab_free() the cached next connection. When the iterator advances it dereferences the freed (and possibly reallocated) slab memory — a use-after-free that can crash the system (denial of service) and, if the slot has been reused, cause the callback to operate on an attacker-influenced object (potential information disclosure or further fault).\n\nnet_tcp_foreach() is reached in production via the net conn network shell command and via net_tcp_close_all_for_iface() on interface-down; the freeing side is driven by ordinary TCP traffic.\n\nThe fix moves the connection/context teardown in tcp_conn_release() inside the tcp_lock critical section and keeps tcp_lock held across the callback in net_tcp_foreach(). The defect was introduced with the modern (TCP2) stack in 2020 and affects releases up to and including v4.4.0."
    },
    {
      "lang": "es",
      "value": "La pila TCP nativa de Zephyr itera la lista global de conexiones en net_tcp_foreach() (subsys/net/ip/tcp.c) usando la macro SYS_SLIST_FOR_EACH_CONTAINER_SAFE, que almacena en caché un puntero al siguiente nodo de la lista. Antes de esta corrección, la función liberaba tcp_lock mientras invocaba la devolución de llamada por conexión y la volvía a adquirir después. Durante esa ventana, una tcp_conn_release() concurrente, ejecutándose en el hilo de la cola de trabajo TCP dedicado cuando el contador de referencias de una conexión cae a cero (por ejemplo, un par remoto cerrando o reiniciando la conexión), puede eliminar y k_mem_slab_free() la siguiente conexión almacenada en caché. Cuando el iterador avanza, desreferencia la memoria de slab liberada (y posiblemente reasignada) - un uso después de liberación que puede bloquear el sistema (denegación de servicio) y, si la ranura ha sido reutilizada, hacer que la devolución de llamada opere sobre un objeto influenciado por el atacante (potencial revelación de información o fallo adicional). Se llega a net_tcp_foreach() en producción a través del comando de shell de red ’net conn’ y a través de net_tcp_close_all_for_iface() al bajar la interfaz; el lado de liberación es impulsado por el tráfico TCP ordinario. La corrección mueve la eliminación de la conexión/contexto en tcp_conn_release() dentro de la sección crítica de tcp_lock y mantiene tcp_lock retenido durante la devolución de llamada en net_tcp_foreach(). El defecto fue introducido con la pila moderna (TCP2) en 2020 y afecta a las versiones hasta la v4.4.0 inclusive."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "zephyrproject",
          "product": "zephyr",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
          "packageName": "zephyr",
          "programFiles": [
            "subsys/net/ip/tcp.c"
          ],
          "versions": [
            {
              "version": "3.6.0",
              "lessThan": "4.3.1",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "4.4.0",
              "lessThan": "4.4.1",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
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        "type": "Secondary",
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          "baseScore": 4.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
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        "type": "Primary",
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          "baseSeverity": "MEDIUM",
          "attackVector": "ADJACENT_NETWORK",
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          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
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    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-15T16:06:39.217653Z",
          "id": "CVE-2026-10634",
          "options": [
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              "exploitation": "none"
            },
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          "role": "CISA Coordinator",
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  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
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  "configurations": [
    {
      "nodes": [
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          "operator": "OR",
          "negate": false,
          "cpeMatch": [
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  "references": [
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/commit/cd85e0e890ab89815c4cbc0a8fbc03a3efa84dc2",
      "source": "[email protected]",
      "tags": [
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    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-6c57-xfhw-j26x",
      "source": "[email protected]",
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        "Patch",
        "Vendor Advisory"
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}