FKIE_CVE-2026-66066

Vulnerability from fkie_nvd - Published: 2026-07-30 19:18 - Updated: 2026-08-04 05:16
Severity
9.5 (Critical) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Summary
Action Pack is a framework for handling and responding to web requests. In versions prior to 7.2.3.2, 8.0.5.1 and 8.1.3.1, Active Storage does not disable libvips operations marked unsafe for untrusted content, allowing a crafted upload to invoke such an operation. Consuming applications are affected when configured to use libvips and accept image uploads from untrusted users. An unauthenticated attacker may exploit this behavior to read arbitrary files accessible to the Rails process, including environment variables and application secrets. Exposure of credentials such as secret_key_base or external-service tokens may enable remote code execution or lateral movement. This issue has been fixed in versions 7.2.3.2, 8.0.5.1 and 8.1.3.1.
References
security-advisories@github.comhttps://github.com/rails/rails/commit/1c01bb587206ee6eb0e1179c2cef96a6a47acb1e
security-advisories@github.comhttps://github.com/rails/rails/commit/349e7a5d5b4b715af1e416db824f3c078a7d59e5
security-advisories@github.comhttps://github.com/rails/rails/commit/d79b7f4aa17dec8ce4960fef05733c8c0c7ef49a
security-advisories@github.comhttps://github.com/rails/rails/releases/tag/v7.2.3.2
security-advisories@github.comhttps://github.com/rails/rails/releases/tag/v8.0.5.1
security-advisories@github.comhttps://github.com/rails/rails/releases/tag/v8.1.3.1
security-advisories@github.comhttps://github.com/rails/rails/security/advisories/GHSA-xr9x-r78c-5hrm
security-advisories@github.comhttps://github.com/rubysec/ruby-advisory-db/blob/master/gems/activestorage/CVE-2026-66066.yml
security-advisories@github.comhttps://thehackernews.com/2026/07/critical-rails-flaw-could-let.html
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2026/07/29/9
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2026/08/01/6
af854a3a-2127-422b-91ae-364da2661108https://ethiack.com/info-hub/research/kindarails2shell-rails-rce-cve-2026-66066
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "rails",
          "vendor": "rails",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 7.2.3.2"
            },
            {
              "status": "affected",
              "version": "\u003e= 8.0.0.beta1, \u003c 8.0.5.1"
            },
            {
              "status": "affected",
              "version": "\u003e= 8.1.0.beta1, \u003c 8.1.3.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Action Pack is a framework for handling and responding to web requests. In versions prior to 7.2.3.2, 8.0.5.1 and 8.1.3.1, Active Storage does not disable libvips operations marked unsafe for untrusted content, allowing a crafted upload to invoke such an operation. Consuming applications are affected when configured to use libvips and accept image uploads from untrusted users. An unauthenticated attacker may exploit this behavior to read arbitrary files accessible to the Rails process, including environment variables and application secrets. Exposure of credentials such as secret_key_base or external-service tokens may enable remote code execution or lateral movement. This issue has been fixed in versions 7.2.3.2, 8.0.5.1 and 8.1.3.1."
    }
  ],
  "id": "CVE-2026-66066",
  "lastModified": "2026-08-04T05:16:40.060",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 9.5,
          "baseSeverity": "CRITICAL",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "HIGH",
          "subIntegrityImpact": "HIGH",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-66066",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-03T00:00:00+00:00",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-30T19:18:35.843",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rails/rails/commit/1c01bb587206ee6eb0e1179c2cef96a6a47acb1e"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rails/rails/commit/349e7a5d5b4b715af1e416db824f3c078a7d59e5"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rails/rails/commit/d79b7f4aa17dec8ce4960fef05733c8c0c7ef49a"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rails/rails/releases/tag/v7.2.3.2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rails/rails/releases/tag/v8.0.5.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rails/rails/releases/tag/v8.1.3.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rails/rails/security/advisories/GHSA-xr9x-r78c-5hrm"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/activestorage/CVE-2026-66066.yml"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://thehackernews.com/2026/07/critical-rails-flaw-could-let.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://www.openwall.com/lists/oss-security/2026/07/29/9"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://www.openwall.com/lists/oss-security/2026/08/01/6"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://ethiack.com/info-hub/research/kindarails2shell-rails-rce-cve-2026-66066"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1188"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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