# CVE-2025-71373: picklescan security bypass via operator.methodcaller

Source: https://junglewise.ai/threats/cve-2025-71373-picklescan-security-bypass-via-operator-methodcaller  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-04. Updated: 2026-07-04  
License: CC BY 4.0 with a link back

CVE-2025-71373 · Severity: high · CVSS 8.1 · Published 2026-07-04

picklescan is a security tool used to scan Python pickle files and machine learning models (like PyTorch) for malicious code. A vulnerability was discovered where the tool fails to detect certain dangerous commands, allowing a specially crafted file to bypass security checks. If a user or automated system trusts the scan results and opens a malicious file, an attacker could execute arbitrary code on the system, potentially leading to a full system compromise or data theft.

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

## Quick answers

**Is CVE-2025-71373 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-71373 being exploited in the wild.

**How severe is CVE-2025-71373?** High severity, with a CVSS score of 8.1, published 4 July 2026.

**Which products and versions are affected?** picklescan (PyPI) ECOSYSTEM:introduced=0,fixed=0.0.33.

**Is there a fix for CVE-2025-71373?** Yes. picklescan (PyPI): upgrade to 0.0.33 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-71373 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2025-71373?** 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.

## How to fix

- picklescan (PyPI): upgrade to 0.0.33 or later

  ```sh
  pip install "picklescan>=0.0.33"
  ```


## Technical details

A protection mechanism failure (CWE-693) exists in picklescan versions prior to 0.0.33. The library's scanning logic fails to identify and flag the 'operator.methodcaller' built-in Python function when embedded in pickle opcodes. An attacker can exploit this by manually crafting a malicious pickle payload that uses this function to trigger arbitrary system commands. Because picklescan reports the file as safe, downstream applications that rely on it for validation will proceed to load the file using 'pickle.load()', resulting in remote code execution. The vulnerability is particularly relevant for environments processing untrusted machine learning models or serialized Python objects.

## Affected products

- picklescan picklescan < 0.0.33

## Identifiers

- CVE-2025-71373
- GHSA-x843-g5mx-g377

## Timeline

- 2025-12-27: advisory: GitHub Security Advisory published
- 2026-07-04: disclosed: NVD publication date

## References

- [https://github.com/mmaitre314/picklescan/security/advisories/GHSA-x843-g5mx-g377](https://github.com/mmaitre314/picklescan/security/advisories/GHSA-x843-g5mx-g377)
- [https://www.vulncheck.com/advisories/picklescan-remote-code-execution-via-operator-methodcaller-detection-bypass](https://www.vulncheck.com/advisories/picklescan-remote-code-execution-via-operator-methodcaller-detection-bypass)

## Related threats

- [picklescan detection bypass via _operator.methodcaller](https://junglewise.ai/threats/cve-2025-71375-picklescan-detection-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)
- [picklescan security bypass via torch.utils.bottleneck in pickle files](https://junglewise.ai/threats/cve-2025-71366-picklescan-security-bypass-via-torch-utils-bottleneck-in-pickle)