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CVE-2026-48998

Full vulnerability record from the local CVENow database.

Description

guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Versions prior to 2.10.2 contain improper Host header validation when parsing raw HTTP request messages and when deriving a server request URI from server variables. An attacker can provide a malformed Host header containing URI authority delimiters, such as `[email protected]`. When the Host value is used to construct a URI, the malformed value can be reinterpreted as URI userinfo and host. This can cause the PSR-7 request URI host to differ from the original Host header value. Applications are affected if they parse attacker-controlled raw HTTP requests with `GuzzleHttp\Psr7\Message::parseRequest()` or the legacy 1.x `GuzzleHttp\Psr7\parse_request()` function, or if they build server requests from attacker-controlled server variables, then rely on the resulting URI host for routing, allow-list checks, or forwarding decisions. In affected forwarding or gateway scenarios, this may cause requests or credentials to be sent to an unintended host. The issue is patched in `2.10.2`. `1.x` is end-of-life and will not receive a patch. Some workarounds are available. Validate the `Host` header as `uri-host [ ":" port ]` before calling `Message::parseRequest()` or legacy `parse_request()` on untrusted HTTP request data, or before deriving routing and forwarding decisions from a parsed request URI. Reject Host values containing userinfo, path, query, or fragment delimiters.

Severity
MEDIUM
CVSS score
5.3 (v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-06-11 13:16:33.133000
Last modified
2026-10-26 11:10:00.157000
View original CVE JSON
{
  "id": "CVE-2026-48998",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-11T13:16:33.133",
  "lastModified": "2026-10-26T11:10:00.157",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Versions prior to 2.10.2 contain improper Host header validation when parsing raw HTTP request messages and when deriving a server request URI from server variables. An attacker can provide a malformed Host header containing URI authority delimiters, such as `[email protected]`. When the Host value is used to construct a URI, the malformed value can be reinterpreted as URI userinfo and host. This can cause the PSR-7 request URI host to differ from the original Host header value. Applications are affected if they parse attacker-controlled raw HTTP requests with `GuzzleHttp\\Psr7\\Message::parseRequest()` or the legacy 1.x `GuzzleHttp\\Psr7\\parse_request()` function, or if they build server requests from attacker-controlled server variables, then rely on the resulting URI host for routing, allow-list checks, or forwarding decisions. In affected forwarding or gateway scenarios, this may cause requests or credentials to be sent to an unintended host. The issue is patched in `2.10.2`. `1.x` is end-of-life and will not receive a patch. Some workarounds are available. Validate the `Host` header as `uri-host [ \":\" port ]` before calling `Message::parseRequest()` or legacy `parse_request()` on untrusted HTTP request data, or before deriving routing and forwarding decisions from a parsed request URI. Reject Host values containing userinfo, path, query, or fragment delimiters."
    },
    {
      "lang": "es",
      "value": "guzzlehttp/psr7 es una implementación de la biblioteca de mensajes HTTP PSR-7 en PHP. Las versiones anteriores a la 2.10.2 contienen una validación incorrecta del encabezado Host al analizar mensajes de solicitud HTTP sin procesar y al derivar una URI de solicitud del servidor a partir de variables del servidor. Un atacante puede proporcionar un encabezado Host malformado que contenga delimitadores de autoridad de URI, como ’[email protected]’. Cuando el valor de Host se utiliza para construir una URI, el valor malformado puede ser reinterpretado como información de usuario y host de la URI. Esto puede hacer que el host de la URI de solicitud PSR-7 difiera del valor original del encabezado Host. Las aplicaciones se ven afectadas si analizan solicitudes HTTP sin procesar controladas por un atacante con ’GuzzleHttp\\Psr7\\Message::parseRequest()’ o la función heredada 1.x ’GuzzleHttp\\Psr7\\parse_request()’, o si construyen solicitudes de servidor a partir de variables de servidor controladas por un atacante, y luego dependen del host de la URI resultante para el enrutamiento, las comprobaciones de lista de permitidos o las decisiones de reenvío. En escenarios de reenvío o de pasarela afectados, esto puede hacer que las solicitudes o credenciales se envíen a un host no deseado. El problema está parcheado en ’2.10.2’. ’1.x’ ha llegado al fin de su vida útil y no recibirá un parche. Algunas soluciones alternativas están disponibles. Valide el encabezado ’Host’ como ’uri-host [ ’:’ puerto ]’ antes de llamar a ’Message::parseRequest()’ o a la función heredada ’parse_request()’ en datos de solicitud HTTP no confiables, o antes de derivar decisiones de enrutamiento y reenvío de una URI de solicitud analizada. Rechace los valores de Host que contengan delimitadores de información de usuario, ruta, consulta o fragmento."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "guzzle",
          "product": "psr7",
          "versions": [
            {
              "version": "< 2.10.2",
              "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:L/I:N/A:N",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-11T16:05:39.189615Z",
          "id": "CVE-2026-48998",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "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-20"
        },
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    },
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
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          "operator": "OR",
          "negate": false,
          "cpeMatch": [
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              "criteria": "cpe:2.3:a:guzzlephp:psr-7:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "2.10.2",
              "matchCriteriaId": "5190DD04-7580-4B6E-BA5A-6B89E0A95A05"
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  "references": [
    {
      "url": "https://github.com/guzzle/psr7/security/advisories/GHSA-34xg-wgjx-8xph",
      "source": "[email protected]",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ]
    }
  ]
}