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CVE-2026-35355

Full vulnerability record from the local CVENow database.

Description

The install utility in uutils coreutils is vulnerable to a Time-of-Check to Time-of-Use (TOCTOU) race condition during file installation. The implementation unlinks an existing destination file and then recreates it using a path-based operation without the O_EXCL flag. A local attacker can exploit the window between the unlink and the subsequent creation to swap the path with a symbolic link, allowing them to redirect privileged writes to overwrite arbitrary system files.

Severity
MEDIUM
CVSS score
6.3 (v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-04-22 17:16:37.993000
Last modified
2026-10-26 21:10:00.170000
View original CVE JSON
{
  "id": "CVE-2026-35355",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-22T17:16:37.993",
  "lastModified": "2026-10-26T21:10:00.170",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The install utility in uutils coreutils is vulnerable to a Time-of-Check to Time-of-Use (TOCTOU) race condition during file installation. The implementation unlinks an existing destination file and then recreates it using a path-based operation without the O_EXCL flag. A local attacker can exploit the window between the unlink and the subsequent creation to swap the path with a symbolic link, allowing them to redirect privileged writes to overwrite arbitrary system files."
    },
    {
      "lang": "es",
      "value": "La utilidad install en uutils coreutils es vulnerable a una condición de carrera de tipo Time-of-Check to Time-of-Use (TOCTOU) durante la instalación de archivos. La implementación desvincula un archivo de destino existente y luego lo recrea utilizando una operación basada en ruta sin la bandera O_EXCL. Un atacante local puede explotar la ventana entre la desvinculación y la creación subsiguiente para intercambiar la ruta con un enlace simbólico, permitiéndoles redirigir escrituras privilegiadas para sobrescribir archivos de sistema arbitrarios."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Uutils",
          "product": "coreutils",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com/uutils",
          "packageName": "coreutils",
          "platforms": [
            "Linux",
            "Unix",
            "macOS"
          ],
          "repo": "https://github.com/uutils/coreutils",
          "versions": [
            {
              "version": "0",
              "lessThan": "0.6.0",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H",
          "baseScore": 6.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "HIGH",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.0,
        "impactScore": 5.2
      }
    ],
    "ssvcV203": [
      {
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        "ssvcData": {
          "timestamp": "2026-04-22T18:01:44.426332Z",
          "id": "CVE-2026-35355",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-367"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:uutils:coreutils:*:*:*:*:*:rust:*:*",
              "versionEndExcluding": "0.6.0",
              "matchCriteriaId": "87C33018-2E08-45B0-B69C-7FC224F7F883"
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  "references": [
    {
      "url": "https://github.com/uutils/coreutils/pull/10067",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Patch"
      ]
    },
    {
      "url": "https://github.com/uutils/coreutils/releases/tag/0.6.0",
      "source": "[email protected]",
      "tags": [
        "Release Notes"
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    },
    {
      "url": "https://github.com/uutils/coreutils/pull/10067",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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}