Vulnerability-Lookup

GHSA-VQ8P-M3WM-GV5F

Vulnerability from github – Published: 2026-10-09 16:26 – Updated: 2026-10-09 16:26

Summary

pyLoad: Lack of Input Size Validation Leads to Denial of Service (DoS) and Process Termination

Details

Description:

The API rpc function in api_blueprint.py handles multipart/form-data uploads by reading the whole content of the uploaded file into memory with file.read(). This occurs before the data is sent to the underlying function. Since there is no size limit set at this point, a large file upload can exhaust the server's available memory which led to process termination.

VulnerableCode & Path:

https://github.com/pyload/pyload/blob/8e447958b8a66c5899775e725a8b90bce6643004/src/pyload/webui/app/blueprints/api_blueprint.py#L73

Steps to Reproduce:

Log in to pyLoad (or use an API key, here i used api to communicate).
Prepare a large file (e.g., 10GB) . bash truncate -s 10G large_file.bin
Send a multipart request to an API function that accepts a file, such as check_online_status_container:

curl -X POST "http://localhost:8000/api/rpc" \
     -H "X-API-Key: YOUR_API_KEY" \
     -F "func=check_online_status_container" \
     -F "container=@large_file.bin"

Monitor the server's memory usage. The process will attempt to allocate memory for the entire file and last the process will be killed by the kernel.

Impact

Denial of Service (DoS): The pyLoad process will be killed by the Operating System's Out-Of-Memory (OOM) killer, or the entire system may become unresponsive due to swap thrashing or memory exhaustion.
Service Instability: Any active downloads or tasks will be interrupted.

Mitigations

Implement File Size Limits: Enforce a maximum size for uploaded files in the web server configuration (e.g., Nginx client_max_body_size).

Severity

6.5 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pyload-ng"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.5.0b3.dev101"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-48484"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-10-09T16:26:53Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "## Description:\nThe API `rpc` function in `api_blueprint.py` handles `multipart/form-data` uploads by reading the whole content of the uploaded file into memory with `file.read()`. This occurs before the data is sent to the underlying function. Since there is no size limit set at this point, a large file upload can exhaust the server\u0027s available memory which led to process termination.\n\n## VulnerableCode \u0026 Path: \nhttps://github.com/pyload/pyload/blob/8e447958b8a66c5899775e725a8b90bce6643004/src/pyload/webui/app/blueprints/api_blueprint.py#L73  \n\n## Steps to Reproduce:\n1. Log in to pyLoad (or use an API key, here i used api to communicate).\n2. Prepare a large file (e.g., 10GB) .\n  ```bash\ntruncate -s 10G large_file.bin\n  ```\n3. Send a multipart request to an API function that accepts a file, such as `check_online_status_container`:\n```bash\ncurl -X POST \"http://localhost:8000/api/rpc\" \\\n     -H \"X-API-Key: YOUR_API_KEY\" \\\n     -F \"func=check_online_status_container\" \\\n     -F \"container=@large_file.bin\"\n```\n4. Monitor the server\u0027s memory usage. The process will attempt to allocate memory for the entire file and last the process will be killed by the kernel.\n\u003cimg width=\"1902\" height=\"610\" alt=\"dos-process-kill-poc\" src=\"https://github.com/user-attachments/assets/2b9bfd0f-5b9f-48dd-983f-f97dfcc358cc\" /\u003e\n\n## Impact\n- **Denial of Service (DoS)**: The pyLoad process will be killed by the Operating System\u0027s Out-Of-Memory (OOM) killer, or the entire system may become unresponsive due to swap thrashing or memory exhaustion.\n- **Service Instability**: Any active downloads or tasks will be interrupted.\n\n## Mitigations\n- **Implement File Size Limits**: Enforce a maximum size for uploaded files in the web server configuration (e.g., Nginx `client_max_body_size`).",
  "id": "GHSA-vq8p-m3wm-gv5f",
  "modified": "2026-10-09T16:26:53Z",
  "published": "2026-10-09T16:26:53Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pyload/pyload/security/advisories/GHSA-vq8p-m3wm-gv5f"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pyload/pyload/commit/461cd66f30fa9e96453fb4d8c5c47467e452363c"
    },
    {
      "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:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "pyLoad: Lack of Input Size Validation Leads to Denial of Service (DoS) and Process Termination"
}

CVE-2026-48484 (GCVE-0-2026-48484)

Vulnerability from cvelistv5 – Published: 2026-10-09 16:26 – Updated: 2026-10-09 16:26

Title

pyLoad: Lack of Input Size Validation Leads to Denial of Service (DoS) and Process Termination

Summary

pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev101, the API `rpc` function in `api_blueprint.py` handles `multipart/form-data` uploads by reading the whole content of the uploaded file into memory with `file.read()`. This occurs before the data is sent to the underlying function. Since there is no size limit set at this point, a large file upload can exhaust the server's available memory which led to process termination. Version 0.5.0b3.dev101 contains a patch.

Severity

6.5 (Medium)


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

CWE

CWE-20 - Improper Input Validation
CWE-400 - Uncontrolled Resource Consumption

Assigner

GitHub_M CNA under the mitre root

CNA scorecard C 72/100 over 7634 records in the last 180 days details

References

3 references

URL	Tags
https://github.com/pyload/pyload/security/advisor…	x_refsource_CONFIRM
https://github.com/pyload/pyload/commit/461cd66f3…	x_refsource_MISC
https://github.com/pyload/pyload/blob/8e447958b8a…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
pyload	pyload	Affected: < 0.5.0b3.dev101

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "pyload",
          "vendor": "pyload",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.5.0b3.dev101"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev101, the API `rpc` function in `api_blueprint.py` handles `multipart/form-data` uploads by reading the whole content of the uploaded file into memory with `file.read()`. This occurs before the data is sent to the underlying function. Since there is no size limit set at this point, a large file upload can exhaust the server\u0027s available memory which led to process termination. Version 0.5.0b3.dev101 contains a patch."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-20",
              "description": "CWE-20: Improper Input Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-400",
              "description": "CWE-400: Uncontrolled Resource Consumption",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-09T16:26:37.728Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/pyload/pyload/security/advisories/GHSA-vq8p-m3wm-gv5f",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/pyload/pyload/security/advisories/GHSA-vq8p-m3wm-gv5f"
        },
        {
          "name": "https://github.com/pyload/pyload/commit/461cd66f30fa9e96453fb4d8c5c47467e452363c",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/pyload/pyload/commit/461cd66f30fa9e96453fb4d8c5c47467e452363c"
        },
        {
          "name": "https://github.com/pyload/pyload/blob/8e447958b8a66c5899775e725a8b90bce6643004/src/pyload/webui/app/blueprints/api_blueprint.py#L73",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/pyload/pyload/blob/8e447958b8a66c5899775e725a8b90bce6643004/src/pyload/webui/app/blueprints/api_blueprint.py#L73"
        }
      ],
      "source": {
        "advisory": "GHSA-vq8p-m3wm-gv5f",
        "discovery": "UNKNOWN"
      },
      "title": "pyLoad: Lack of Input Size Validation Leads to Denial of Service (DoS) and Process Termination"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-48484",
    "datePublished": "2026-10-09T16:26:37.728Z",
    "dateReserved": "2026-05-21T15:33:08.291Z",
    "dateUpdated": "2026-10-09T16:26:37.728Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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