# Picklescan remote code execution via incomplete deny-list

Source: https://junglewise.ai/threats/picklescan-remote-code-execution-via-incomplete-deny-list-af63e977  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-17. Updated: 2026-06-18  
License: CC BY 4.0 with a link back

Severity: critical · CVSS 9.8 · Published 2026-06-17

Picklescan is a security tool used to scan Python pickle files for malicious code. A vulnerability in its detection logic allows specially crafted files to bypass security checks by using unblocked functions. If an attacker successfully bypasses these checks, they can execute arbitrary commands on the system scanning the file, potentially leading to a full system compromise.

Technologies: [picklescan (PyPI)](https://junglewise.ai/threats/technologies/picklescan). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Critical severity, with a CVSS score of 9.8, published 17 June 2026.

**Which products and versions are affected?** picklescan (PyPI) < 0.0.33.

**Is there a fix for This vulnerability?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is This vulnerability attacked?** It is attacked over the network, in a software library.

**Am I affected?** Check whether you run picklescan (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

Picklescan before version 0.0.33 contains an incomplete deny-list (CWE-184) that fails to block the 'pydoc.locate' and 'operator.methodcaller' functions. An attacker can leverage 'pydoc.locate' to dynamically resolve modules and 'operator.methodcaller' to execute methods like 'os.system' within a pickle file. Because these functions were not explicitly flagged as dangerous, the tool treats them as safe or suspicious rather than blocking them. This allows a remote attacker to achieve arbitrary code execution (RCE) when the malicious pickle file is deserialized by a user or system relying on Picklescan for validation. The issue is resolved in version 0.0.33 by implementing a wildcard block on the affected modules.

## Affected products

- mmaitre314 picklescan < 0.0.33

## Timeline

- 2025-12-26: advisory: Original GHSA-84r2-jw7c-4r5q published by maintainer
- 2026-06-17: disclosed: CVE-2025-71320 published to NVD
- 2026-06-18: other: Duplicate advisory GHSA-6v84-v468-3c7f withdrawn

## References

- [https://github.com/mmaitre314/picklescan/security/advisories/GHSA-84r2-jw7c-4r5q](https://github.com/mmaitre314/picklescan/security/advisories/GHSA-84r2-jw7c-4r5q)
- [https://www.vulncheck.com/advisories/picklescan-remote-code-execution-via-incomplete-disallowed-inputs](https://www.vulncheck.com/advisories/picklescan-remote-code-execution-via-incomplete-disallowed-inputs)

## Related threats

- [picklescan detection bypass via _operator.methodcaller](https://junglewise.ai/threats/cve-2025-71375-picklescan-detection-bypass-via-operator-methodcaller)
- [picklescan security bypass via operator.methodcaller](https://junglewise.ai/threats/cve-2025-71373-picklescan-security-bypass-via-operator-methodcaller)
- [Picklescan detection bypass via numpy getlincoef gadget](https://junglewise.ai/threats/cve-2025-71372-picklescan-detection-bypass-via-numpy-getlincoef-gadget)
- [picklescan safety check bypass via PyTorch decoder basichandlers](https://junglewise.ai/threats/cve-2025-71369-picklescan-safety-check-bypass-via-pytorch-decoder-basichandlers)
- [picklescan security bypass via _operator.attrgetter function call](https://junglewise.ai/threats/cve-2025-71367-picklescan-security-bypass-via-operator-attrgetter-function-call)