FKIE_CVE-2026-33170

Vulnerability from fkie_nvd - Published: 2026-03-24 00:16 - Updated: 2026-06-17 10:37
Severity
6.1 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Summary
Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, `SafeBuffer#%` does not propagate the `@html_unsafe` flag to the newly created buffer. If a `SafeBuffer` is mutated in place (e.g. via `gsub!`) and then formatted with `%` using untrusted arguments, the result incorrectly reports `html_safe? == true`, bypassing ERB auto-escaping and possibly leading to XSS. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.
References
security-advisories@github.comhttps://github.com/rails/rails/commit/50d732af3b7c8aaf63cbcca0becbc00279b215b7Patch
security-advisories@github.comhttps://github.com/rails/rails/commit/6e8a81108001d58043de9e54a06fca58962fc2dbPatch
security-advisories@github.comhttps://github.com/rails/rails/commit/c1ad0e8e1972032f3395853a5e99cea035035bebPatch
security-advisories@github.comhttps://github.com/rails/rails/releases/tag/v7.2.3.1Release Notes
security-advisories@github.comhttps://github.com/rails/rails/releases/tag/v8.0.4.1Release Notes
security-advisories@github.comhttps://github.com/rails/rails/releases/tag/v8.1.2.1Release Notes
security-advisories@github.comhttps://github.com/rails/rails/security/advisories/GHSA-89vf-4333-qx8vVendor Advisory
Impacted products
Vendor Product Version
rubyonrails rails *
rubyonrails rails *
rubyonrails rails *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "activesupport",
          "vendor": "rails",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 8.1.0.beta1, \u003c 8.1.2.1"
            },
            {
              "status": "affected",
              "version": "\u003e= 8.0.0.beta1, \u003c 8.0.4.1"
            },
            {
              "status": "affected",
              "version": "\u003c 7.2.3.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "D9DC6CB9-DC6C-4CBB-9806-3936ADBC8F1B",
              "versionEndExcluding": "7.2.3.1",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "FA8791E1-8B96-43F6-A3EC-A7E60D700330",
              "versionEndExcluding": "8.0.4.1",
              "versionStartIncluding": "8.0.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "978E0135-D14B-41DE-87E4-CF059A23E189",
              "versionEndExcluding": "8.1.2.1",
              "versionStartIncluding": "8.1.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, `SafeBuffer#%` does not propagate the `@html_unsafe` flag to the newly created buffer. If a `SafeBuffer` is mutated in place (e.g. via `gsub!`) and then formatted with `%` using untrusted arguments, the result incorrectly reports `html_safe? == true`, bypassing ERB auto-escaping and possibly leading to XSS. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch."
    },
    {
      "lang": "es",
      "value": "Active Support es un conjunto de herramientas de bibliotecas de soporte y extensiones del n\u00facleo de Ruby extra\u00eddas del framework de Rails. Antes de las versiones 8.1.2.1, 8.0.4.1 y 7.2.3.1, \u0027SafeBuffer#%\u0027 no propaga el flag \u0027@html_unsafe\u0027 al b\u00fafer reci\u00e9n creado. Si un \u0027SafeBuffer\u0027 es mutado in situ (p. ej., a trav\u00e9s de \u0027gsub!\u0027) y luego formateado con \u0027%\u0027 usando argumentos no confiables, el resultado informa incorrectamente que \u0027html_safe? == true\u0027, omitiendo el auto-escapado de ERB y posiblemente llevando a XSS. Las versiones 8.1.2.1, 8.0.4.1 y 7.2.3.1 contienen un parche."
    }
  ],
  "id": "CVE-2026-33170",
  "lastModified": "2026-06-17T10:37:04.360",
  "metrics": {
    "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": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "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": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "PASSIVE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/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": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-33170",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-03-25T19:20:16.086015Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-03-24T00:16:28.287",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/rails/rails/commit/50d732af3b7c8aaf63cbcca0becbc00279b215b7"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/rails/rails/commit/6e8a81108001d58043de9e54a06fca58962fc2db"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/rails/rails/commit/c1ad0e8e1972032f3395853a5e99cea035035beb"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/rails/rails/releases/tag/v7.2.3.1"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/rails/rails/releases/tag/v8.0.4.1"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/rails/rails/releases/tag/v8.1.2.1"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://github.com/rails/rails/security/advisories/GHSA-89vf-4333-qx8v"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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