CVE-2026-47272

Estado: AplazadaAlta (7.1)—

pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.0, the pusb_pad_compare() function in src/pad.c only verified that the user-side pad (~/.pamusb/device.pad) could be read, but did not enforce that the system-side pad (the pad file on the USB device) was also present and readable. If the user-side pad was deleted or unreadable, the function returned a failure that was treated as non-fatal in certain code paths, allowing authentication to succeed without the USB device being verified. A local user can delete their own ~/.pamusb/device.pad to remove the USB device requirement and authenticate without the physical device. This vulnerability is fixed in 0.9.0.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Puntuación base: 7.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.17%
Percentil entre todas las CVEs puntuadas: 5
Fecha de la puntuación: 5/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Impacto principalT1078 Valid Accountsstealth · persistence · privilege escalation · initial access90 %
Impacto secundarioT1098 Account Manipulationpersistence · privilege escalation75 %

AV:L, PR:L, UI:N indica escalada local. Atacante elimina su pad para saltar autenticación USB y obtener acceso con sus propias credenciales (T1078) o manipular cuentas (T1098).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

User Account Management Privileged Account Management Multi-factor Authentication Application Developer Guidance Active Directory Configuration User Training

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

PAM USB — PAM USB^AI

CWE

CWE-287, CWE-908

Referencias

https://github.com/mcdope/pam_usb/security/advisories/GHSA-vx6f-rrqr-j87c

JSON original (NVD)

Mostrar

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  "id": "CVE-2026-47272",
  "cveTags": [],
  "metrics": {
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      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-47272",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-05-28T12:52:21.630173Z"
        }
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.2,
        "exploitabilityScore": 1.8
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    {
      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "mcdope",
          "product": "pam_usb",
          "versions": [
            {
              "status": "affected",
              "version": "< 0.9.0"
            }
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  "published": "2026-05-27T20:16:39.747",
  "references": [
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      "url": "https://github.com/mcdope/pam_usb/security/advisories/GHSA-vx6f-rrqr-j87c",
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      "value": "pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.0, the pusb_pad_compare() function in src/pad.c only verified that the user-side pad (~/.pamusb/device.pad) could be read, but did not enforce that the system-side pad (the pad file on the USB device) was also present and readable. If the user-side pad was deleted or unreadable, the function returned a failure that was treated as non-fatal in certain code paths, allowing authentication to succeed without the USB device being verified. A local user can delete their own ~/.pamusb/device.pad to remove the USB device requirement and authenticate without the physical device. This vulnerability is fixed in 0.9.0."
    }
  ],
  "lastModified": "2026-06-17T10:54:27.240",
  "sourceIdentifier": "security-advisories@github.com"
}