picklescan remote code execution via obfuscated eval call

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

picklescan is a security tool designed to detect malicious code within Python pickle files. A vulnerability in versions before 1.0.1 allows attackers to bypass these security checks by using simple code obfuscation techniques. If an organization relies on an affected version of picklescan to vet untrusted files, an attacker could successfully deliver and execute malicious code on their systems, leading to a full system compromise.

Technologies: picklescan (PyPI). 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) < 1.0.1.
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 1.0.1 is vulnerable to a bypass of its security scanning logic due to improper handling of obfuscated Python objects. Specifically, the scanner fails to identify malicious 'builtins.eval' calls when they are nested under other callable objects using 'getattr'. An attacker can craft a malicious pickle file that utilizes this obfuscation to evade detection by the tool. When the resulting pickle file is loaded by a victim, the hidden payload executes arbitrary code. This is categorized as an unsafe deserialization vulnerability (CWE-502). The issue is resolved in version 1.0.1.

Affected products

  • mmaitre314 picklescan < 1.0.1

Timeline

  • 2026-02-02: advisory: Original GHSA-9m3x-qqw2-h32h published
  • 2026-06-17: disclosed: NVD publication of CVE-2026-53874
  • 2026-06-18: other: Duplicate advisory GHSA-j6c9-qvp8-699f withdrawn

References

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