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GHSA-9W2P-RH8C-V9G5

Vulnerability from github – Published: 2023-12-09 00:39 – Updated: 2024-11-22 20:21
VLAI
Summary
Local Privilege Escalation in Windows
Details

Impact

A PyInstaller built application, elevated as a privileged process, may be tricked by an unprivileged attacker into deleting files the unprivileged user does not otherwise have access to.

A user is affected if all the following are satisfied:

  • The user runs an application containing either matplotlib or win32com.
  • The application is ran as administrator (or at least a user with higher privileges than the attacker).
  • The user's temporary directory is not locked to that specific user (most likely due to TMP/TEMP environment variables pointing to an unprotected, arbitrary, non default location).
  • Either:
  • The attacker is able to very carefully time the replacement of a temporary file with a symlink. This switch must occur exactly between shutil.rmtree()'s builtin symlink check and the deletion itself
  • The application was built with Python 3.7.x or earlier which has no protection against Directory Junctions links

Patches

The vulnerability has been addressed in https://github.com/pyinstaller/pyinstaller/pull/7827 which corresponds to pyinstaller >= 5.13.1

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

No workaround, although the attack complexity becomes much higher if the application is built with Python >= 3.8.0.

Severity
8.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pyinstaller"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.13.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-49797"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-379",
      "CWE-732"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-12-09T00:39:46Z",
    "nvd_published_at": "2023-12-09T01:15:07Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nA PyInstaller built application, elevated as a privileged process, may be tricked by an unprivileged attacker into deleting files the unprivileged user does not otherwise have access to.\n\nA user is affected if **all** the following are satisfied:\n\n* The user runs an application containing either `matplotlib` or `win32com`.\n* The application is ran as administrator (or at least a user with higher privileges than the attacker).\n* The user\u0027s temporary directory is not locked to that specific user (most likely due to `TMP`/`TEMP` environment variables pointing to an unprotected, arbitrary, non default location).\n* Either:\n  - The attacker is able to very carefully time the replacement of a temporary file with a symlink. This switch must occur exactly between [`shutil.rmtree()`\u0027s builtin symlink check](https://github.com/python/cpython/blob/0fb18b02c8ad56299d6a2910be0bab8ad601ef24/Lib/shutil.py#L623) and the deletion itself\n  - The application was built with Python 3.7.x or earlier which has no protection against Directory Junctions links\n\n### Patches\n\nThe vulnerability has been addressed in https://github.com/pyinstaller/pyinstaller/pull/7827 which corresponds to `pyinstaller \u003e= 5.13.1`\n\n### Workarounds\n_Is there a way for users to fix or remediate the vulnerability without upgrading?_\n\nNo workaround, although the attack complexity becomes much higher if the application is built with Python \u003e= 3.8.0.",
  "id": "GHSA-9w2p-rh8c-v9g5",
  "modified": "2024-11-22T20:21:21Z",
  "published": "2023-12-09T00:39:46Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pyinstaller/pyinstaller/security/advisories/GHSA-9w2p-rh8c-v9g5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-49797"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pyinstaller/pyinstaller/pull/7827"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pyinstaller/pyinstaller"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyinstaller/PYSEC-2023-292.yaml"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/blob/0fb18b02c8ad56299d6a2910be0bab8ad601ef24/Lib/shutil.py#L623"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2K2XIQLEMZIKUQUOWNDYWTEWYQTKMAN7"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ISRWT34FAF23PUOLVZ7RVWBZMWPDR5U7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Local Privilege Escalation in Windows"
}



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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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