CVE-2026-34839

{
  "id": "CVE-2026-34839",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-21T00:16:27.910",
  "lastModified": "2026-10-26T21:10:00.170",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.4, the Glances web server exposes a REST API (`/api/4/*`) that is accessible without authentication and allows cross-origin requests from any origin due to a permissive CORS policy (`Access-Control-Allow-Origin: *`). This allows a malicious website to read sensitive system information from a running Glances instance in the victim’s browser, leading to cross-origin data exfiltration. While a previous advisory exists for XML-RPC CORS issues, this report demonstrates that the REST API (`/api/4/*`) is also affected and exposes significantly more sensitive data. Version 4.5.4 patches the issue."
    },
    {
      "lang": "es",
      "value": "Glances es una herramienta de monitoreo de sistema de código abierto multiplataforma. Antes de la versión 4.5.4, el servidor web de Glances expone una API REST (’/api/4/*’) que es accesible sin autenticación y permite solicitudes de origen cruzado desde cualquier origen debido a una política CORS permisiva (’Access-Control-Allow-Origin: *’). Esto permite a un sitio web malicioso leer información sensible del sistema de una instancia de Glances en ejecución en el navegador de la víctima, lo que lleva a la exfiltración de datos de origen cruzado. Aunque existe un aviso anterior para problemas de CORS de XML-RPC, este informe demuestra que la API REST (’/api/4/*’) también está afectada y expone datos significativamente más sensibles. La versión 4.5.4 corrige el problema."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "nicolargo",
          "product": "glances",
          "versions": [
            {
              "version": "< 4.5.4",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
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        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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",
          "baseScore": 7.7,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "PROOF_OF_CONCEPT",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "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": "UNCHANGED",
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          "availabilityImpact": "NONE"
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      }
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        "ssvcData": {
          "timestamp": "2026-04-21T19:37:18.710681Z",
          "id": "CVE-2026-34839",
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              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
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              "technicalImpact": "partial"
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          "role": "CISA Coordinator",
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  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
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          "value": "CWE-200"
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        {
          "lang": "en",
          "value": "CWE-306"
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        {
          "lang": "en",
          "value": "CWE-942"
        }
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    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-306"
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  "configurations": [
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  "references": [
    {
      "url": "https://github.com/nicolargo/glances/commit/fdfb977b1d91b5e410bc06c4e19f8bedb0005ce9",
      "source": "[email protected]",
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        "Patch"
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    },
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      "source": "[email protected]",
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        "Vendor Advisory"
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      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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}