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FKIE_CVE-2021-39320

Vulnerability from fkie_nvd - Published: 2021-09-01 15:15 - Updated: 2026-06-17 04:03
Severity
6.1 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Summary
The underConstruction plugin <= 1.18 for WordPress echoes out the raw value of `$GLOBALS['PHP_SELF']` in the ucOptions.php file. On certain configurations including Apache+modPHP, this makes it possible to use it to perform a reflected Cross-Site Scripting attack by injecting malicious code in the request path.
References
security@wordfence.comhttps://wpscan.com/vulnerability/49ae1df0-d6d2-4cbb-9a9d-bf3599429875Third Party Advisory
security@wordfence.comhttps://www.wordfence.com/vulnerability-advisories/#CVE-2021-39320Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://wpscan.com/vulnerability/49ae1df0-d6d2-4cbb-9a9d-bf3599429875Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39320Third Party Advisory
Impacted products
Vendor Product Version
underconstruction_project underconstruction *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "underConstruction",
          "vendor": "Noah Kagan",
          "versions": [
            {
              "lessThanOrEqual": "1.18",
              "status": "affected",
              "version": "1.18",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "security@wordfence.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:underconstruction_project:underconstruction:*:*:*:*:*:wordpress:*:*",
              "matchCriteriaId": "B67F8F68-1894-42D4-BB91-50AFA863CDEB",
              "versionEndExcluding": "1.19",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The underConstruction plugin \u003c= 1.18 for WordPress echoes out the raw value of `$GLOBALS[\u0027PHP_SELF\u0027]` in the ucOptions.php file. On certain configurations including Apache+modPHP, this makes it possible to use it to perform a reflected Cross-Site Scripting attack by injecting malicious code in the request path."
    },
    {
      "lang": "es",
      "value": "El plugin underConstruction versiones anteriores a 1.18 incluy\u00e9ndola, para WordPress se hace eco del valor bruto de \"$GLOBALS[\"PHP_SELF\"]\" en el archivo ucOptions.php. En determinadas configuraciones, incluyendo Apache+modPHP, esto permite usarlo para llevar acabo un ataque de tipo Cross-Site Scripting reflejado, inyectando c\u00f3digo malicioso en la ruta de petici\u00f3n"
    }
  ],
  "id": "CVE-2021-39320",
  "lastModified": "2026-06-17T04:03:32.767",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 4.3,
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.1,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 2.7,
        "source": "security@wordfence.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-39320",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-05-05T14:50:39.494520Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2021-09-01T15:15:12.653",
  "references": [
    {
      "source": "security@wordfence.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://wpscan.com/vulnerability/49ae1df0-d6d2-4cbb-9a9d-bf3599429875"
    },
    {
      "source": "security@wordfence.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39320"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://wpscan.com/vulnerability/49ae1df0-d6d2-4cbb-9a9d-bf3599429875"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39320"
    }
  ],
  "sourceIdentifier": "security@wordfence.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "security@wordfence.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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