Fickling is a Python pickling decompiler and static analyzer. Fickling versions up to and including 0.1.6 do not treat Python's cProfile module as unsafe. Because of this, a malicious pickle that uses cProfile.run() is classified as SUSPICIOUS instead of OVERTLY_MALICIOUS. If a user relies on Fickling's output to decide whether a pickle is safe to deserialize, this misclassification can lead them to execute attacker-controlled code on their system. This affects any workflow or product that uses Fickling as a security gate for pickle deserialization. This issue has been patched in version 0.1.7.

Affected: PyPI: fickling

# Fickling's assessment

`cProfile` was added to the list of unsafe imports (https://github.com/trailofbits/fickling/commit/dc8ae12966edee27a78fe05c5745171a2b138d43).

# Original report

## Description

### Summary

Fickling versions up to and including 0.1.6 do not treat Python's `cProfile` module as unsafe. Because of this, a malicious pickle that uses `cProfile.run()` is classified as SUSPICIOUS instead of OVERTLY_MALICIOUS.

If a user relies on Fickling's output to decide whether a pickle is safe to deserialize, this misclassification can lead them to execute attacker-controlled code on their system.

This affects any workflow or product that uses Fickling as a security gate for pickle deserialization.

### Details

The `cProfile` module is missing from fickling's block list of unsafe module imports in `fickling/analysis.py`. This is the same root cause as CVE-2025-67748 (pty) and CVE-2025-67747 (marshal/types).

Incriminated source code:

- File: `fickling/analysis.py` - Class: `UnsafeImports` - Issue: The blocklist does not include `cProfile`, `cProfile.run`, or `cProfile.runctx`

Reference to similar fix:

- PR #187 added `pty` to the blocklist to fix CVE-2025-67748 - PR #108 documented the blocklist approach - The same fix pattern should be applied for `cProfile`

How the bypass works:

1. Attacker creates a pickle using `cProfile.run()` in `__reduce__` 2. `cProfile.run()` accepts a Python code string and executes it directly (C-accelerated version of profile.run) 3.…

Affected: PyPI: fickling

# Fickling's assessment

`cProfile` was added to the list of unsafe imports (https://github.com/trailofbits/fickling/commit/dc8ae12966edee27a78fe05c5745171a2b138d43).

# Original report

## Description

### Summary

Fickling versions up to and including 0.1.6 do not treat Python's `cProfile` module as unsafe. Because of this, a malicious pickle that uses `cProfile.run()` is classified as SUSPICIOUS instead of OVERTLY_MALICIOUS.

If a user relies on Fickling's output to decide whether a pickle is safe to deserialize, this misclassification can lead them to execute attacker-controlled code on their system.

This affects any workflow or product that uses Fickling as a security gate for pickle deserialization.

### Details

The `cProfile` module is missing from fickling's block list of unsafe module imports in `fickling/analysis.py`. This is the same root cause as CVE-2025-67748 (pty) and CVE-2025-67747 (marshal/types).

Incriminated source code:

- File: `fickling/analysis.py` - Class: `UnsafeImports` - Issue: The blocklist does not include `cProfile`, `cProfile.run`, or `cProfile.runctx`

Reference to similar fix:

- PR #187 added `pty` to the blocklist to fix CVE-2025-67748 - PR #108 documented the blocklist approach - The same fix pattern should be applied for `cProfile`

How the bypass works:

1. Attacker creates a pickle using `cProfile.run()` in `__reduce__` 2. `cProfile.run()` accepts a Python code string and executes it directly (C-accelerated version of profile.run) 3.…