---
id: CVE-2025-61765
aliases:
  - GHSA-g8c6-8fjj-2r4m
  - PYSEC-2026-1854
title: >-
  python-socketio vulnerable to arbitrary Python code execution (RCE) through
  malicious pickle deserialization in certain multi-server depl…
summary: >-
  python-socketio vulnerable to arbitrary Python code execution (RCE) through
  malicious pickle deserialization in certain multi-server deployments
severity: medium
cvss: 6.4
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L'
vendor: python-socketio
product: python-socketio
ecosystem: pip
affected:
  - 'python-socketio >= 0.8.0, < 5.14.0'
patched:
  - python-socketio 5.14.0
published: '2025-10-07'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:50:29.882047738Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-g8c6-8fjj-2r4m'
references:
  - url: >-
      https://github.com/miguelgrinberg/python-socketio/security/advisories/GHSA-g8c6-8fjj-2r4m
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2025-61765'
  - url: >-
      https://github.com/miguelgrinberg/python-socketio/commit/53f6be094257ed81476b0e212c8cddd6d06ca39a
  - url: 'https://github.com/miguelgrinberg/python-socketio'
  - url: >-
      https://www.bluerock.io/post/cve-2025-61765-bluerock-discovers-critical-rce-in-socket-io-ecosystem
tags:
  - osv
  - pip
  - exploit-available
epss: 0.00482
epssPercentile: 0.38883
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/locus-x64/CVE-2025-61765_PoC'
  checkedAt: '2026-09-25T08:20:46.356Z'
exploitAvailable: true
ingestedAt: '2026-07-08T18:25:49.673Z'
---

## Overview

### Summary
A remote code execution vulnerability in python-socketio versions prior to 5.14.0 allows attackers to execute arbitrary Python code through malicious pickle deserialization in multi-server deployments on which the attacker previously gained access to the message queue that the servers use for internal communications.

### Details
When Socket.IO servers are configured to use a message queue backend such as Redis for inter-server communication, messages sent between the servers are encoded using the `pickle` Python module. When a server receives one of these messages through the message queue, it assumes it is trusted and immediately deserializes it.

The vulnerability stems from deserialization of messages using Python's `pickle.loads()` function. Having previously obtained access to the message queue, the attacker can send a python-socketio server a crafted pickle payload that executes arbitrary code during deserialization via Python's `__reduce__` method.

### Impact
This vulnerability only affects deployments with a compromised message queue. The attack can lead to the attacker executing random code in the context of, and with the privileges of a Socket.IO server process. 

Single-server systems that do not use a message queue, and multi-server systems with a secure message queue are not vulnerable.

### Remediation
In addition to making sure standard security practices are followed in the deployment of the message queue, users of the python-socketio package can upgrade to version 5.14.0 or newer, which remove the `pickle` module and use the much safer JSON encoding for inter-server messaging.

## Affected packages

- `python-socketio >= 0.8.0, < 5.14.0`

## Remediation

Upgrade to a patched release:

- `python-socketio 5.14.0`