CVE-2026-48981

{
  "id": "CVE-2026-48981",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-18T20:16:14.407",
  "lastModified": "2026-10-26T11:10:00.157",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "pam_usb provides hardware authentication for Linux using ordinary removable media. In versions prior to 0.9.2, pam_usb calls xmlReadFile() with flags=0 when loading the configuration file, allowing libxml2 to process external entity references (XXE), potentially making outbound network connections or local file reads at XML parse time from the context of the authenticating process. The vulnerability requires the configuration file to contain crafted XML entity references. Since pam_usb.conf is root-owned, direct exploitation requires prior write access to the config, but the defence-in-depth impact is significant given that pam_usb.so runs in setuid contexts (sudo, su). This issue has been fixed in version 0.9.2."
    },
    {
      "lang": "es",
      "value": "pam_usb proporciona autenticación de hardware para Linux utilizando medios extraíbles ordinarios. En versiones anteriores a la 0.9.2, pam_usb llama a xmlReadFile() con flags=0 al cargar el archivo de configuración, permitiendo a libxml2 procesar referencias a entidades externas (XXE), lo que podría permitir realizar conexiones de red salientes o lecturas de archivos locales en el momento del análisis XML desde el contexto del proceso de autenticación. La vulnerabilidad requiere que el archivo de configuración contenga referencias a entidades XML manipuladas. Dado que pam_usb.conf es propiedad de root, la explotación directa requiere acceso de escritura previo a la configuración, pero el impacto en la defensa en profundidad es significativo dado que pam_usb.so se ejecuta en contextos setuid (sudo, su). Este problema ha sido solucionado en la versión 0.9.2."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "mcdope",
          "product": "pam_usb",
          "versions": [
            {
              "version": "< 0.9.2",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:L",
          "baseScore": 6.7,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "HIGH",
          "privilegesRequired": "HIGH",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "LOW",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 0.8,
        "impactScore": 5.3
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-22T15:19:25.463710Z",
          "id": "CVE-2026-48981",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-611"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/mcdope/pam_usb/releases/tag/0.9.2",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/mcdope/pam_usb/security/advisories/GHSA-96vv-r4wc-28c2",
      "source": "[email protected]"
    }
  ]
}