GHSA-3329-ghmp-jmv5 — picklescan
Fix: mmaitre314/picklescan#53GHSA-3329-ghmp-jmv5 is a Deserialization of Untrusted Data vulnerability in picklescan. A fix is available for picklescan — see the affected versions and patch details below.
Picklescan is vulnerable to RCE through missing detection when calling numpy.f2py.crackfortran.myeval
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for GHSA-3329-ghmp-jmv5.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
picklescanReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Picklescan uses numpy.f2py.crackfortran.myeval, which is a function in numpy to execute remote pickle files.
Details
The attack payload executes in the following steps:
- First, the attacker crafts the payload by calling the numpy.f2py.crackfortran.myeval function in its reduce method
- Then, when the victim checks whether the pickle file is safe by using the Picklescan library and this library doesn't detect any dangerous functions, they decide to use pickle.load() on this malicious pickle file, thus leading to remote code execution.
PoC
class RCE:
def __reduce__(self):
from numpy.f2py.crackfortran import myeval
return (myeval, ("os.system('ls')",))
Impact
Any organization or individual relying on picklescan to detect malicious pickle files inside PyTorch models. Attackers can embed malicious code in pickle file that remains undetected but executes when the pickle file is loaded. Attackers can distribute infected pickle files across ML models, APIs, or saved Python objects.
Report by
Pinji Chen ([email protected]) from the NISL lab (https://netsec.ccert.edu.cn/about) at Tsinghua University, Guanheng Liu ([email protected]).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | picklescan | all versions | 0.0.33pip install --upgrade 'picklescan==0.0.33' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for picklescan, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update picklescan to 0.0.33 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3329-ghmp-jmv5 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-3329-ghmp-jmv5 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-3329-ghmp-jmv5. 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-3329-ghmp-jmv5 in your dependencies?
O3 Security finds GHSA-3329-ghmp-jmv5 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.