CVE-2025-7346: Pyload ng PyLoad Is Vulnerable To Attacks Vulnerability

HIGH
Advisory Identifier: GHSA-x698-5hjm-w2m5
CVSS 7.5
CWE-284 CWE-290
Published
Advisory Summary

CVE-2025-7346 is a HIGH (CVSS 7.5) pyload is vulnerable to attacks vulnerability (CWE-284: Improper Access Control) affecting Pyload ng libraries in the PyPI ecosystem. The issue involves pyload is vulnerable to attacks that bypass localhost restrictions, enabling the creation of arbitrary packages. Remediation is available in the latest vendor maintenance releases.

CVE-2025-7346 at a Glance

CVE Identifier CVE-2025-7346
GHSA Identifier GHSA-x698-5hjm-w2m5
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-284: Improper Access Control
Affected Product Pyload ng
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2025-7346

To remediate this vulnerability, upgrade all affected Pyload ng dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

pyload-ng fixed: Latest secure release
pip install pyload-ng>=Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

pip show pyload-ng

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2025-7346, inspect your installed packages using pip:

pip show pyload-ng

Analyze the terminal output to locate any version of Pyload ng in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The pip show pyload-ng command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-284: Improper Access Control, where the product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. In Pyload ng, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary Any unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. ### Details Any unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. This is done by changing the `Host` header to the value of `127.0.0.1:9666`. ### PoC The application has middleware that prevents access to several routes by checking whether the `Host` header has a specific value. We bypassed this restriction. https://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L21-L36 ```python #: decorator def local_check(func): @wraps(func) def wrapper(*args, **kwargs): remote_addr = flask.request.environ.get("REMOTE_ADDR", "0") http_host = flask.request.environ.get("HTTP_HOST", "0") if remote_addr in ("127.0.0.1", "::ffff:127.0.0.1", "::1", "localhost") or http_host in ( "127.0.0.1:9666", "[::1]:9666", ): return func(*args, **kwargs) else: return "Forbidden", 403 return wrapper ``` Below we see that the '/flash/add' endpoint uses the middleware above. https://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L56-L58C11 ```python @bp.route("/flash/add", methods=["POST"], endpoint="add") @local_check def add(): ``` Notice how we are not authorized to access this endpoint when sending a request. ![image](https://user-images.githubusercontent.com/44903767/294935526-64217d91-c0d1-4d8f-963f-cedfa8dc9034.png) However, if we set the `Host` header to be `127.0.0.1:9666`, we notice the request returns `success`. ![image](https://user-images.githubusercontent.com/44903767/294933755-43ad3826-0e94-4ba5-acf0-48f11670cbc6.png) Checking the front end as an admin, we now see that this did indeed succeed. ![image](https://user-images.githubusercontent.com/44903767/294934431-5d024c75-59dc-47b6-8887-b14ae91e320f.png) ### Impact An unauthenticated user can perform actions that should only be available to authenticated users.

CVE-2025-7346 Affected Pyload ng Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
pyload-ng
PyPI
≤ 0.5.0b3.dev88

References

Frequently Asked Questions

What is CVE-2025-7346?
CVE-2025-7346 is a security vulnerability in Pyload ng involving pyLoad is vulnerable to attacks that bypass localhost restrictions, enabling the creation of arbitrary packages under CWE-284: Improper Access Control.
Which Pyload ng versions are affected?
Affected versions include releases prior to current release patches across affected packages: pyload-ng.
What version fixes CVE-2025-7346?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is pyload-ng affected?
Yes, pyload-ng is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2025-7346?
CVE-2025-7346 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
What CWE is associated with CVE-2025-7346?
CVE-2025-7346 is classified under CWE-284: Improper Access Control (The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.).
How can I check PyPI dependencies for CVE-2025-7346?
Run the dependency tree command: 'pip show pyload-ng'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-x698-5hjm-w2m5",
  "modified" : "2025-07-08T23:38:45Z",
  "published" : "2025-07-08T21:36:52Z",
  "aliases" : [ "CVE-2025-7346" ],
  "summary" : "pyLoad is vulnerable to attacks that bypass localhost restrictions, enabling the creation of arbitrary packages",
  "details" : "### Summary\nAny unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages.\n\n### Details\nAny unauthenticated attacker can bypass the localhost restrictions posed by the application and utilize this to create arbitrary packages. This is done by changing the `Host` header to the value of `127.0.0.1:9666`.\n\n### PoC\nThe application has middleware that prevents access to several routes by checking whether the `Host` header has a specific value. We bypassed this restriction.\n\nhttps://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L21-L36\n```python\n#: decorator\ndef local_check(func):\n    @wraps(func)\n    def wrapper(*args, **kwargs):\n        remote_addr = flask.request.environ.get(\"REMOTE_ADDR\", \"0\")\n        http_host = flask.request.environ.get(\"HTTP_HOST\", \"0\")\n\n        if remote_addr in (\"127.0.0.1\", \"::ffff:127.0.0.1\", \"::1\", \"localhost\") or http_host in (\n            \"127.0.0.1:9666\",\n            \"[::1]:9666\",\n        ):\n            return func(*args, **kwargs)\n        else:\n            return \"Forbidden\", 403\n\n    return wrapper\n```\n\nBelow we see that the '/flash/add' endpoint uses the middleware above.\n\nhttps://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L56-L58C11\n```python\n@bp.route(\"/flash/add\", methods=[\"POST\"], endpoint=\"add\")\n@local_check\ndef add():\n```\n\nNotice how we are not authorized to access this endpoint when sending a request.\n![image](https://user-images.githubusercontent.com/44903767/294935526-64217d91-c0d1-4d8f-963f-cedfa8dc9034.png)\n\nHowever, if we set the `Host` header to be `127.0.0.1:9666`, we notice the request returns `success`.\n![image](https://user-images.githubusercontent.com/44903767/294933755-43ad3826-0e94-4ba5-acf0-48f11670cbc6.png)\n\nChecking the front end as an admin, we now see that this did indeed succeed.\n![image](https://user-images.githubusercontent.com/44903767/294934431-5d024c75-59dc-47b6-8887-b14ae91e320f.png)\n\n### Impact\nAn unauthenticated user can perform actions that should only be available to authenticated users.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "pyload-ng"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.5.0b3.dev88"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/pyload/pyload/security/advisories/GHSA-x698-5hjm-w2m5"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pyload/pyload/commit/f4e2d12416ba2dfac7b036d5c8d6dab5461b9840"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/pyload/pyload"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L21-L36"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pyload/pyload/blob/4159a1191ec4fe6d927e57a9c4bb8f54e16c381d/src/pyload/webui/app/blueprints/cnl_blueprint.py#L56-L58C11"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-284", "CWE-290" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-07-08T21:36:52Z",
    "nvd_published_at" : null
  }
}