FKIE_CVE-2026-48984

Vulnerability from fkie_nvd - Published: 2026-06-18 18:16 - Updated: 2026-06-22 17:56
Severity
4.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Summary
pam_usb provides hardware authentication for Linux using ordinary removable media. In versions 0.9.1 and below, the xfree() memory release helper in calls free() without first zeroing the buffer contents, releasing heap-allocated buffers containing sensitive data — including one-time pad bytes read from disk — without clearing, leaving the sensitive content in freed heap memory until it happens to be overwritten by a subsequent allocation. On a system where a use-after-free condition exists, or where a heap inspection primitive becomes available, this could allow recovery of pad values or other authentication material from freed memory regions. This is a defence-in-depth requirement consistent with prior hardening work in this codebase (GHSA-vx6f-rrqr-j87c applied explicit_bzero to some pad paths; this issue generalises the pattern to the central deallocation helper).
References
security-advisories@github.comhttps://github.com/mcdope/pam_usb/releases/tag/0.9.2
security-advisories@github.comhttps://github.com/mcdope/pam_usb/security/advisories/GHSA-rmp6-wfrq-wrrc
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "pam_usb",
          "vendor": "mcdope",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.9.2"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "pam_usb provides hardware authentication for Linux using ordinary removable media. In versions 0.9.1 and below, the xfree() memory release helper in calls free() without first zeroing the buffer contents, releasing heap-allocated buffers containing sensitive data \u2014 including one-time pad bytes read from disk \u2014 without clearing, leaving the sensitive content in freed heap memory until it happens to be overwritten by a subsequent allocation. On a system where a use-after-free condition exists, or where a heap inspection primitive becomes available, this could allow recovery of pad values or other authentication material from freed memory regions. This is a defence-in-depth requirement consistent with prior hardening work in this codebase (GHSA-vx6f-rrqr-j87c applied explicit_bzero to some pad paths; this issue generalises the pattern to the central deallocation helper)."
    }
  ],
  "id": "CVE-2026-48984",
  "lastModified": "2026-06-22T17:56:35.757",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "NONE",
          "baseScore": 4.7,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.0,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-48984",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-18T18:47:42.610995Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-18T18:16:19.493",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/mcdope/pam_usb/releases/tag/0.9.2"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/mcdope/pam_usb/security/advisories/GHSA-rmp6-wfrq-wrrc"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-14"
        },
        {
          "lang": "en",
          "value": "CWE-226"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.