FKIE_CVE-2019-18684

Vulnerability from fkie_nvd - Published: 2019-11-04 16:15 - Updated: 2026-06-17 02:25
Severity
7.0 (High) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
Sudo through 1.8.29 allows local users to escalate to root if they have write access to file descriptor 3 of the sudo process. This occurs because of a race condition between determining a uid, and the setresuid and openat system calls. The attacker can write "ALL ALL=(ALL) NOPASSWD:ALL" to /proc/#####/fd/3 at a time when Sudo is prompting for a password. NOTE: This has been disputed due to the way Linux /proc works. It has been argued that writing to /proc/#####/fd/3 would only be viable if you had permission to write to /etc/sudoers. Even with write permission to /proc/#####/fd/3, it would not help you write to /etc/sudoers
References
cve@mitre.orghttps://gist.github.com/oxagast/51171aa161074188a11d96cbef884bbdExploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://gist.github.com/oxagast/51171aa161074188a11d96cbef884bbdExploit, Third Party Advisory
Impacted products
Vendor Product Version
sudo_project sudo *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:sudo_project:sudo:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B9079F2B-965B-4A0A-8FC0-105AC3C5DD62",
              "versionEndIncluding": "1.8.29",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [
    {
      "sourceIdentifier": "cve@mitre.org",
      "tags": [
        "disputed"
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Sudo through 1.8.29 allows local users to escalate to root if they have write access to file descriptor 3 of the sudo process. This occurs because of a race condition between determining a uid, and the setresuid and openat system calls. The attacker can write \"ALL ALL=(ALL) NOPASSWD:ALL\" to /proc/#####/fd/3 at a time when Sudo is prompting for a password. NOTE: This has been disputed due to the way Linux /proc works. It has been argued that writing to /proc/#####/fd/3 would only be viable if you had permission to write to /etc/sudoers. Even with write permission to /proc/#####/fd/3, it would not help you write to /etc/sudoers"
    },
    {
      "lang": "es",
      "value": "** EN DISPUTA ** Sudo versiones hasta 1.8.29, permite a los usuarios locales escalar a root si poseen acceso de escritura al descriptor de archivo 3 del proceso sudo. Esto se presenta debido a una condici\u00f3n de carrera entre la determinaci\u00f3n de un uid y las llamadas al sistema setresuid y openat. El atacante puede escribir \"ALL ALL=(ALL) NOPASSWD:ALL\" en /proc/#####/fd/3 en un momento cuando Sudo solicita una contrase\u00f1a. NOTA: Esto se ha disputado debido a la forma en que funciona Linux /proc. Se ha argumentado que escribir en /proc/#####/fd/3 solo ser\u00eda viable si tuviera permiso para escribir en /etc/sudoers. Incluso con permiso de escritura en /proc/#####/fd/3, no le ayudar\u00eda a escribir en /etc/sudoers."
    }
  ],
  "id": "CVE-2019-18684",
  "lastModified": "2026-06-17T02:25:17.877",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "LOCAL",
          "authentication": "NONE",
          "availabilityImpact": "COMPLETE",
          "baseScore": 6.9,
          "confidentialityImpact": "COMPLETE",
          "integrityImpact": "COMPLETE",
          "vectorString": "AV:L/AC:M/Au:N/C:C/I:C/A:C",
          "version": "2.0"
        },
        "exploitabilityScore": 3.4,
        "impactScore": 10.0,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.0,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.0,
        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2019-11-04T16:15:11.437",
  "references": [
    {
      "source": "cve@mitre.org",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://gist.github.com/oxagast/51171aa161074188a11d96cbef884bbd"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://gist.github.com/oxagast/51171aa161074188a11d96cbef884bbd"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-362"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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