---
id: CVE-2025-71349
aliases:
  - GHSA-5qwp-399c-mjwf
title: >-
  Picklescan has a missing detection when calling built-in python
  trace.Trace.run
summary: >-
  Picklescan has a missing detection when calling built-in python
  trace.Trace.run
severity: medium
vendor: picklescan
product: picklescan
ecosystem: pip
affected:
  - picklescan < 0.0.29
patched:
  - picklescan 0.0.29
published: '2025-08-26'
updated: '2026-07-08'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-5qwp-399c-mjwf'
references:
  - url: >-
      https://github.com/mmaitre314/picklescan/security/advisories/GHSA-5qwp-399c-mjwf
  - url: >-
      https://github.com/mmaitre314/picklescan/commit/aecd11be98702caa9ba9b12189d91ad596a36114
  - url: 'https://github.com/mmaitre314/picklescan'
tags:
  - osv
  - pip
epss: 0.00613
epssPercentile: 0.47134
ingestedAt: '2026-07-08T18:25:46.052Z'
---

## Overview

### Summary

Using trace.Trace.run, 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 trace.Trace.run 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

```
class EvilTraceRun:
    def __reduce__(self):
        from trace import Trace
        payload = "__import__('os').system('whoami')"
        return Trace.run, (Trace(), payload)
```

### 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

https://github.com/FredericDT
https://github.com/Qhaoduoyu

## Affected packages

- `picklescan < 0.0.29`

## Remediation

Upgrade to a patched release:

- `picklescan 0.0.29`