picklescan before version 0.0.33 fails to detect malicious pickle files that use the numpy.f2py.crackfortran.param_eval function in reduce methods. When such a pickle is deserialized, the embedded code runs without detection, giving attackers remote code execution on the host. This is a classic pickling vulnerability (CWE-502) that threatens the confidentiality, integrity, and availability of the system that processes the payload.

The vulnerability affects the picklescan tool, specifically versions before 0.0.33. Any application that incorporates picklescan to load or analyze untrusted pickle data is potentially exposed, including third‑party software that relies on picklescan for data handling or threat detection.

The base CVSS score of 7.6 indicates a high severity vulnerability, while the EPSS score of less than 1% suggests that exploitation attempts are currently rare. The issue is not listed in the CISA KEV catalog. Attackers can achieve remote code execution by supplying a crafted pickle file that triggers the undiscovered numpy.f2py.crackfortran.param_eval path during deserialization. Based on the description, it is inferred that successful exploitation requires an application to deserialize external pickle data, and that execution would affect the system; the scale of impact would depend on the privileges of the process executing picklescan.