CVE-2025-71320: picklescan — CRITICAL

picklescan before 0.0.33 contains an incomplete deny-list that fails to block pydoc.locate and operator.methodcaller functions, allowing attackers to bypass security checks. Remote attackers can craft malicious pickle files using these unblocked functions to achieve arbitrary code execution when...

Full CISO analysis pending enrichment.

What systems are affected?

Package	Ecosystem	Vulnerable Range	Patched
picklescan	pip	—	No patch
412 3 dependents Pushed 1mo ago 82% patched ~12d to patch Full package profile →

Do you use picklescan? You're affected.

How severe is it?

CVSS 3.1

9.8 / 10

EPSS

N/A

Exploitation Status

No known exploitation

Sophistication

N/A

What is the attack surface?

AV Network

AC Low

PR None

UI None

S Unchanged

C High

I High

A High

What should I do?

No patch available

Monitor for updates. Consider compensating controls or temporary mitigations.

Which compliance frameworks are affected?

Compliance analysis pending. Sign in for full compliance mapping when available.

Frequently Asked Questions

What is CVE-2025-71320?

picklescan before 0.0.33 contains an incomplete deny-list that fails to block pydoc.locate and operator.methodcaller functions, allowing attackers to bypass security checks. Remote attackers can craft malicious pickle files using these unblocked functions to achieve arbitrary code execution when the pickle is deserialized.

Is CVE-2025-71320 actively exploited?

No confirmed active exploitation of CVE-2025-71320 has been reported, but organizations should still patch proactively.

How to fix CVE-2025-71320?

No patch is currently available. Monitor vendor advisories for updates.

What is the CVSS score for CVE-2025-71320?

CVE-2025-71320 has a CVSS v3.1 base score of 9.8 (CRITICAL).

What are the technical details?

Original Advisory

picklescan before 0.0.33 contains an incomplete deny-list that fails to block pydoc.locate and operator.methodcaller functions, allowing attackers to bypass security checks. Remote attackers can craft malicious pickle files using these unblocked functions to achieve arbitrary code execution when the pickle is deserialized.

Weaknesses (CWE)

CWE-184 Incomplete List of Disallowed Inputs

CWE-184 — Incomplete List of Disallowed Inputs: The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete.

[Implementation] Do not rely exclusively on detecting disallowed inputs. There are too many variants to encode a character, especially when different environments are used, so there is a high likelihood of missing some variants. Only use detection of disallowed inputs as a mechanism for detecting suspicious activity. Ensure that you are using other protection mechanisms that only identify "good" input - such as lists of allowed inputs - and ensure that you are properly encoding your outputs.

Source: MITRE CWE corpus.