GHSA-4XH5-X5GV-QWPH

Vulnerability from github – Published: 2025-09-24 15:31 – Updated: 2025-11-03 18:31
VLAI?
Summary
pip's fallback tar extraction doesn't check symbolic links point to extraction directory
Details

Summary

In the fallback extraction path for source distributions, pip used Python’s tarfile module without verifying that symbolic/hard link targets resolve inside the intended extraction directory. A malicious sdist can include links that escape the target directory and overwrite arbitrary files on the invoking host during pip install.

Impact

Successful exploitation enables arbitrary file overwrite outside the build/extraction directory on the machine running pip. This can be leveraged to tamper with configuration or startup files and may lead to further code execution depending on the environment, but the direct, guaranteed impact is integrity compromise on the vulnerable system.

Conditions

The issue is triggered when installing an attacker-controlled sdist (e.g., from an index or URL) and the fallback extraction code path is used. No special privileges are required beyond running pip install; active user action is necessary.

Remediation

The fix is available starting in pip 25.3. Using a Python interpreter that implements the safe-extraction behavior described by PEP 706 provides additional defense in depth for other tarfile issues but is not a substitute for upgrading pip for this specific flaw.

Severity ?
5.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 25.2"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "pip"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "25.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-8869"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-59"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-09-24T20:04:58Z",
    "nvd_published_at": "2025-09-24T15:15:41Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nIn the fallback extraction path for source distributions, `pip` used Python\u2019s `tarfile` module without verifying that symbolic/hard link targets resolve inside the intended extraction directory. A malicious sdist can include links that escape the target directory and overwrite arbitrary files on the invoking host during `pip install`.\n\n### Impact\n\nSuccessful exploitation enables arbitrary file overwrite outside the build/extraction directory on the machine running `pip`. This can be leveraged to tamper with configuration or startup files and may lead to further code execution depending on the environment, but the direct, guaranteed impact is integrity compromise on the vulnerable system.\n\n### Conditions\n\nThe issue is triggered when installing an attacker-controlled sdist (e.g., from an index or URL) and the fallback extraction code path is used. No special privileges are required beyond running `pip install`; active user action is necessary.\n\n### Remediation\n\nThe [fix](https://github.com/pypa/pip/pull/13550) is available starting in pip `25.3`. Using a Python interpreter that implements the safe-extraction behavior described by **PEP 706** provides additional defense in depth for other `tarfile` issues but is not a substitute for upgrading pip for this specific flaw.",
  "id": "GHSA-4xh5-x5gv-qwph",
  "modified": "2025-11-03T18:31:43Z",
  "published": "2025-09-24T15:31:14Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-8869"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/pip/pull/13550"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/pip/commit/f2b92314da012b9fffa36b3f3e67748a37ef464a"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pypa/pip"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00028.html"
    },
    {
      "type": "WEB",
      "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/IF5A3GCJY3VH7BVHJKOWOJFKTW7VFQEN"
    },
    {
      "type": "WEB",
      "url": "https://pip.pypa.io/en/stable/news/#v25-2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "pip\u0027s fallback tar extraction doesn\u0027t check symbolic links point to extraction directory"
}


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  • 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.