CVE-2025-62515: 
Python vulnerability analysis and mitigation

CVE-2025-62515 affects pyquokka, a framework for making data lakes work for time series. In versions 0.3.1 and prior, a critical remote code execution vulnerability was discovered in the FlightServer class. The vulnerability was disclosed on October 17, 2025, affecting all versions up to and including 0.3.2. This security flaw allows attackers to execute arbitrary code remotely through unsafe deserialization of pickle data (GitHub Advisory).

The vulnerability exists in the FlightServer class where the doaction() method directly uses pickle.loads() to deserialize action bodies received from Flight clients without any sanitization or validation. The vulnerable code is located in pyquokka/flight.py at line 283. Additional vulnerability points exist in the cachegarbagecollect, doput, and do_get functions where pickle.loads is used to deserialize untrusted remote data. The vulnerability has been assigned a CVSS v3.1 score of 9.8 (Critical) with a vector string of CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, indicating network accessibility, low attack complexity, and no required privileges or user interaction (GitHub Advisory).

The vulnerability allows attackers to achieve complete system compromise, enabling data exfiltration, lateral movement within the network, denial of service attacks, and installation of persistent backdoors. When FlightServer is configured to listen on 0.0.0.0, attackers across the entire network can perform arbitrary remote code execution by sending malicious pickled payloads through the set_configs action (GitHub Advisory).

Several mitigation strategies are recommended: 1) Replace pickle.loads() with safer alternatives such as JSON serialization for simple data structures or Protocol Buffers/MessagePack for complex data. 2) If pickle must be used, implement a custom Unpickler with a restricted find_class() method that only allows whitelisted classes. 3) Bind to localhost (127.0.0.1) instead of 0.0.0.0 if the service is intended for internal use only. 4) Implement proper authentication and authorization mechanisms (GitHub Advisory).