Vulnerability · Published Nov 25, 2025 · Assigned by GitHub_M
CVE-2025-62703Fugue is Vulnerable to Remote Code Execution by Pickle Deserialization via FlaskRPCServer
High 8.8
In plain English
A high-severity unsafe deserialization in fugue from fugue-project. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 56% of all known vulnerabilities).
Official description
Fugue is a unified interface for distributed computing that lets users execute Python, Pandas, and SQL code on Spark, Dask, and Ray with minimal rewrites. In version 0.9.2 and prior, there is a remote code execution vulnerability by pickle deserialization via FlaskRPCServer. The Fugue framework implements an RPC server system for distributed computing operations. In the core functionality of the RPC server implementation, I found that the _decode() function in fugue/rpc/flask.py directly uses cloudpickle.loads() to deserialize data without any sanitization. This creates a remote code execution vulnerability when malicious pickle data is processed by the RPC server. The vulnerability exists in the RPC communication mechanism where the client can send arbitrary serialized Python objects that will be deserialized on the server side, allowing attackers to execute arbitrary code on the victim's machine. This issue has been patched via commit 6f25326.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | fugue | no fix listed | GHSA-xv5p-fjw5-vrj6 |
| PyPI | fugue | no fix listed | PYSEC-2026-1399 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| fugue-project | fugue | <= 0.9.2 |
Weakness: CWE-502 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H