CVE-2025-71373 picklescan CVE debrief

Who should care

Organizations using picklescan for validation should prioritize updating to version 0.0.33 or later. Developers and security teams responsible for validating and securing pickle files are particularly affected. Given the high severity and potential for remote code execution, immediate attention is necessary to prevent potential exploitation.

Technical summary

The vulnerability in picklescan before version 0.0.33 stems from its inability to detect operator.methodcaller function calls within pickle files. Picklescan is a tool used for validating and securing pickle files, which are Python objects serialized into byte streams. The operator.methodcaller function is a built-in Python function that allows for dynamic method invocation. By failing to detect this function, picklescan allows malicious pickle files to be validated as safe, even though they can execute arbitrary code when loaded. Attackers can craft malicious pickle payloads that utilize operator.methodcaller to execute code, potentially leading to remote code execution on systems that rely on picklescan for validation. This issue is exacerbated by the fact that pickle files can be easily distributed and loaded, making it a vector for potential attacks. The Common Vulnerability Scoring System (CVSS) score for this vulnerability is 7.6, indicating high severity.

Defensive priority

High priority should be given to updating picklescan to version 0.0.33 or later. In the interim, organizations should restrict the loading of untrusted pickle files and monitor for suspicious pickle file activity.

Recommended defensive actions

• Update picklescan to version 0.0.33 or later immediately.
• Restrict the loading of untrusted pickle files until the update can be applied.
• Monitor for suspicious pickle file activity and potential exploitation attempts.
• Review and update security policies regarding the handling and validation of pickle files.
• Consider implementing additional security measures such as sandboxing or isolation for pickle file validation.

Evidence notes

The evidence for this CVE comes primarily from the NVD and the vendor's advisory. The CVE was published on 2026-07-04T02:16:23.220Z. The vulnerability was disclosed by Vulncheck, and references include advisories from GitHub and Vulncheck's own website. The CVSS score is 7.6, indicating high severity.

Official resources