GHSA-fqq6-7vqf-w3fg
Picklescan is missing detection when calling built-in python doctest.debug_script
Blast Radius
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Description
Summary
Using doctest.debug_script function, which is a built-in python library function to execute remote pickle file.
Details
The attack payload executes in the following steps:
First, the attacker craft the payload by calling to doctest.debug_script function in reduce method Then when the victim after checking whether the pickle file is safe by using Picklescan library and this library doesn't dectect any dangerous functions, decide to pickle.load() this malicious pickle file, thus lead to remote code execution.
PoC
from doctest import debug_script
class EvilDoctestDebugScript:
def __reduce__(self):
# debug_script(src, pm=True) -> exec(src, ...)
return debug_script, ("__import__('os').system('whoami')", True)
Impact
Who is impacted? Any organization or individual relying on picklescan to detect malicious pickle files inside PyTorch models. What is the impact? Attackers can embed malicious code in pickle file that remains undetected but executes when the pickle file is loaded. Supply Chain Attack: Attackers can distribute infected pickle files across ML models, APIs, or saved Python objects.
Corresponding
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | picklescan | all versions | 0.0.30 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for picklescan. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update picklescan to 0.0.30 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fqq6-7vqf-w3fg is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-fqq6-7vqf-w3fg is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-fqq6-7vqf-w3fg. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-fqq6-7vqf-w3fg in your dependencies?
O3 detects GHSA-fqq6-7vqf-w3fg across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.