CVE-2026-8023

{
  "id": "CVE-2026-8023",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-29T23:16:43.777",
  "lastModified": "2026-10-25T21:10:00.770",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Zephyr's HTTP server (subsys/net/lib/http) provides a static-filesystem resource type (HTTP_RESOURCE_TYPE_STATIC_FS, available when CONFIG_FILE_SYSTEM is enabled) that serves files from a configured root directory. Before this fix, both the HTTP/1 and HTTP/2 front-ends placed the raw, attacker-controlled request path into client->url_buffer (assembled in on_url() for HTTP/1 and copied verbatim from the :path pseudo-header for HTTP/2) without resolving ./.. segments. The static-FS handler then built the on-disk filename by directly concatenating the configured root with that raw URL (snprintk(fname, ..., \"%s%s\", static_fs_detail->fs_path, client->url_buffer) at http_server_http1.c:603 and http_server_http2.c:490) and opened it with fs_open(fname, FS_O_READ). Because the handler is reached via wildcard/leading-dir (fnmatch FNM_LEADING_DIR) or fallback resource matching, a request such as GET /<prefix>/../../<file> is dispatched to the handler and, after the underlying filesystem (e.g. LittleFS/FAT) resolves the .. segments, escapes the configured web root, letting an unauthenticated remote client read arbitrary readable files on the mounted volume (information disclosure). The HTTP server requires no TLS or authentication to reach this path. The fix adds http_server_remove_dot_segments(), which canonicalizes the path portion of the URL before resource lookup in both protocol handlers, neutralizing the traversal. Affects releases v4.0.0 through v4.4.0 for deployments that register a static-filesystem resource."
    },
    {
      "lang": "es",
      "value": "El servidor HTTP de Zephyr (subsys/net/lib/http) proporciona un tipo de recurso de sistema de archivos estático (HTTP_RESOURCE_TYPE_STATIC_FS, disponible cuando CONFIG_FILE_SYSTEM está habilitado) que sirve archivos desde un directorio raíz configurado. Antes de esta corrección, ambos front-ends HTTP/1 y HTTP/2 colocaban la ruta de solicitud cruda, controlada por el atacante, en client-url_buffer (ensamblada en on_url() para HTTP/1 y copiada textualmente del pseudo-encabezado :path para HTTP/2) sin resolver los segmentos ./... El gestor de FS estático luego construía el nombre de archivo en disco concatenando directamente la raíz configurada con esa URL cruda (snprintk(fname, ..., ’%s%s’, static_fs_detail-fs_path, client-url_buffer) en http_server_http1.c:603 y http_server_http2.c:490) y lo abría con fs_open(fname, FS_O_READ). Debido a que se accede al gestor a través de comodín/directorio principal (fnmatch FNM_LEADING_DIR) o coincidencia de recurso de respaldo, una solicitud como GET /<prefix/.. / .. / <file se envía al gestor y, después de que el sistema de archivos subyacente (p. ej., LittleFS/FAT) resuelve los segmentos .., escapa de la raíz web configurada, permitiendo que un cliente remoto no autenticado lea archivos arbitrarios legibles en el volumen montado (revelación de información). El servidor HTTP no requiere TLS ni autenticación para alcanzar esta ruta. La corrección añade http_server_remove_dot_segments(), que canoniza la porción de la ruta de la URL antes de la búsqueda de recursos en ambos gestores de protocolo, neutralizando la transversalidad. Afecta a las versiones v4.0.0 hasta v4.4.0 para implementaciones que registran un recurso de sistema de archivos estático."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "zephyrproject",
          "product": "zephyr",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
          "packageName": "zephyr",
          "programFiles": [
            "subsys/net/lib/http/headers/server_internal.h",
            "subsys/net/lib/http/http_server_core.c",
            "subsys/net/lib/http/http_server_http1.c",
            "subsys/net/lib/http/http_server_http2.c"
          ],
          "versions": [
            {
              "version": "4.0.0",
              "lessThan": "4.3.1",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "4.4.0",
              "lessThan": "4.4.2",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
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        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-30T13:11:39.509082Z",
          "id": "CVE-2026-8023",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
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  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
        },
        {
          "lang": "en",
          "value": "CWE-23"
        }
      ]
    },
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
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          "negate": false,
          "cpeMatch": [
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  "references": [
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/commit/f4a423c98554f209c5d2f22f041822422c9263b8",
      "source": "[email protected]",
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    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-hch3-53g6-jj3h",
      "source": "[email protected]",
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        "Vendor Advisory"
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    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-hch3-53g6-jj3h",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
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}