CVE-2026-8106

{
  "id": "CVE-2026-8106",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-07T22:16:37.377",
  "lastModified": "2026-10-26T20:10:00.160",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A reflected HTML injection vulnerability was identified in the GitHub Enterprise Server Management Console login page that could allow credential theft. The redirect_to query parameter on the /setup/unlock endpoint was reflected into an HTML attribute without proper sanitization, enabling an attacker to inject a form element that could capture administrator credentials. Exploitation required an administrator to click a crafted link and enter their credentials. This vulnerability affected GitHub Enterprise Server versions 3.19.1 through 3.19.5 and 3.20.0 through 3.20.1, and was fixed in versions 3.19.6 and 3.20.2. This vulnerability was reported via the GitHub Bug Bounty program."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de inyección HTML reflejada fue identificada en la página de inicio de sesión de la Consola de Administración de GitHub Enterprise Server que podría permitir el robo de credenciales. El parámetro de consulta redirect_to en el endpoint /setup/unlock fue reflejado en un atributo HTML sin la sanitización adecuada, permitiendo a un atacante inyectar un elemento de formulario que podría capturar credenciales de administrador. La explotación requería que un administrador hiciera clic en un enlace manipulado e introdujera sus credenciales. Esta vulnerabilidad afectó a las versiones de GitHub Enterprise Server 3.19.1 a 3.19.5 y 3.20.0 a 3.20.1, y fue corregida en las versiones 3.19.6 y 3.20.2. Esta vulnerabilidad fue reportada a través del programa de recompensas por errores de GitHub."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "GitHub",
          "product": "Enterprise Server",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "3.19.1",
              "lessThanOrEqual": "3.19.5",
              "versionType": "semver",
              "status": "affected",
              "changes": [
                {
                  "at": "3.19.6",
                  "status": "unaffected"
                }
              ]
            },
            {
              "version": "3.20.0",
              "lessThanOrEqual": "3.20.1",
              "versionType": "semver",
              "status": "affected",
              "changes": [
                {
                  "at": "3.20.2",
                  "status": "unaffected"
                }
              ]
            },
            {
              "version": "3.19.0",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "3.21.0",
              "versionType": "semver",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
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        "source": "[email protected]",
        "type": "Secondary",
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          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "privilegesRequired": "NONE",
          "userInteraction": "ACTIVE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
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          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
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          "scope": "CHANGED",
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          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
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      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-08T13:07:24.192705Z",
          "id": "CVE-2026-8106",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
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  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
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  "configurations": [
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      "nodes": [
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  "references": [
    {
      "url": "https://docs.github.com/en/[email protected]/admin/release-notes#3.19.6",
      "source": "[email protected]",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
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      "url": "https://docs.github.com/en/[email protected]/admin/release-notes#3.20.2",
      "source": "[email protected]",
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}