« Volver al listado

CVE-2021-21708

Estado: ModificadaCrítica (9.8)—

En PHP versiones 7.4.x anteriores a 7.4.28, versiones 8.0.x anteriores a 8.0.16 y versiones 8.1.x anteriores a 8.1.3, cuando son usados funciones de filtrado con el filtro FILTER_VALIDATE_FLOAT y los límites mínimo/máximo, si el filtro falla, se presenta la posibilidad de que sea activado el uso de la memoria asignada después de liberarla, lo que puede resultar en un bloqueo, y potencialmente la sobreescritura de otros trozos de memoria y RCE. Este problema afecta a: el código que usa FILTER_VALIDATE_FLOAT con límites mín/máx.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

PHP — PHP

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2021-21708",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 6.8,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 6.4,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 8.6,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security@php.net",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 8.2,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "LOW",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 4.2,
        "exploitabilityScore": 3.9
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 9.8,
          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 3.9
      }
    ]
  },
  "affected": [
    {
      "source": "security@php.net",
      "affectedData": [
        {
          "vendor": "PHP Group",
          "product": "PHP",
          "versions": [
            {
              "status": "affected",
              "version": "7.4.x",
              "lessThan": "7.4.28",
              "versionType": "custom"
            },
            {
              "status": "affected",
              "version": "8.0.X",
              "lessThan": "8.0.16",
              "versionType": "custom"
            },
            {
              "status": "affected",
              "version": "8.1.X",
              "lessThan": "8.1.3",
              "versionType": "custom"
            }
          ]
        }
      ]
    }
  ],
  "published": "2022-02-27T08:15:06.817",
  "references": [
    {
      "url": "https://bugs.php.net/bug.php?id=81708",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch",
        "Vendor Advisory"
      ],
      "source": "security@php.net"
    },
    {
      "url": "https://security.gentoo.org/glsa/202209-20",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "security@php.net"
    },
    {
      "url": "https://security.netapp.com/advisory/ntap-20220325-0004/",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "security@php.net"
    },
    {
      "url": "https://bugs.php.net/bug.php?id=81708",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch",
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://security.gentoo.org/glsa/202209-20",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://security.netapp.com/advisory/ntap-20220325-0004/",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security@php.net",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    },
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In PHP versions 7.4.x below 7.4.28, 8.0.x below 8.0.16, and 8.1.x below 8.1.3, when using filter functions with FILTER_VALIDATE_FLOAT filter and min/max limits, if the filter fails, there is a possibility to trigger use of allocated memory after free, which can result it crashes, and potentially in overwrite of other memory chunks and RCE. This issue affects: code that uses FILTER_VALIDATE_FLOAT with min/max limits."
    },
    {
      "lang": "es",
      "value": "En PHP versiones 7.4.x anteriores a 7.4.28, versiones 8.0.x anteriores a 8.0.16 y versiones 8.1.x anteriores a 8.1.3, cuando son usados funciones de filtrado con el filtro FILTER_VALIDATE_FLOAT y los límites mínimo/máximo, si el filtro falla, se presenta la posibilidad de que sea activado el uso de la memoria asignada después de liberarla, lo que puede resultar en un bloqueo, y potencialmente la sobreescritura de otros trozos de memoria y RCE. Este problema afecta a: el código que usa FILTER_VALIDATE_FLOAT con límites mín/máx."
    }
  ],
  "lastModified": "2026-06-17T03:36:02.283",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:php:php:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "07B88F14-3867-49F4-8BE6-64E1D98927AB",
              "versionEndExcluding": "7.4.28",
              "versionStartIncluding": "7.4.0"
            },
            {
              "criteria": "cpe:2.3:a:php:php:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "AC80C1D0-09AC-43B1-A653-7ECFB37DC42E",
              "versionEndExcluding": "8.0.16",
              "versionStartIncluding": "8.0.0"
            },
            {
              "criteria": "cpe:2.3:a:php:php:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B7E795BC-F012-4904-B445-D76E358EC66D",
              "versionEndExcluding": "8.1.3",
              "versionStartIncluding": "8.1.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security@php.net"
}