id: PYSEC-2026-1854
published: "2026-07-07T16:03:06.734448Z"
modified: "2026-07-07T17:25:14.820810Z"
aliases:
- CVE-2025-61765
- GHSA-g8c6-8fjj-2r4m
summary: python-socketio vulnerable to arbitrary Python code execution (RCE) through malicious pickle deserialization in certain multi-server deployments
details: "### Summary\nA 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.\n\n### Details\nWhen 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.\n\nThe 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.\n\n### Impact\nThis 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. \n\nSingle-server systems that do not use a message queue, and multi-server systems with a secure message queue are not vulnerable.\n\n### Remediation\nIn 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:
- package:
    name: python-socketio
    ecosystem: PyPI
    purl: pkg:pypi/python-socketio
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: 0.8.0
    - fixed: 5.14.0
  versions:
  - 0.8.0
  - 0.8.1
  - 0.8.2
  - 0.9.0
  - 0.9.1
  - 0.9.2
  - "1.0"
  - "1.1"
  - "1.2"
  - "1.3"
  - "1.4"
  - 1.4.1
  - 1.4.2
  - 1.4.3
  - 1.4.4
  - 1.5.0
  - 1.5.1
  - 1.6.0
  - 1.6.1
  - 1.6.2
  - 1.6.3
  - 1.7.0
  - 1.7.1
  - 1.7.2
  - 1.7.3
  - 1.7.4
  - 1.7.5
  - 1.7.6
  - 1.7.7
  - 1.8.0
  - 1.8.1
  - 1.8.2
  - 1.8.3
  - 1.8.4
  - 1.9.0
  - 2.0.0
  - 2.1.0
  - 2.1.1
  - 2.1.2
  - 3.0.0
  - 3.0.1
  - 3.1.0
  - 3.1.1
  - 3.1.2
  - 4.0.0
  - 4.0.1
  - 4.0.2
  - 4.0.3
  - 4.1.0
  - 4.2.0
  - 4.2.1
  - 4.3.0
  - 4.3.1
  - 4.4.0
  - 4.5.0
  - 4.5.1
  - 4.6.0
  - 4.6.1
  - 5.0.0
  - 5.0.1
  - 5.0.2
  - 5.0.3
  - 5.0.4
  - 5.1.0
  - 5.10.0
  - 5.11.0
  - 5.11.1
  - 5.11.2
  - 5.11.3
  - 5.11.4
  - 5.12.0
  - 5.12.1
  - 5.13.0
  - 5.2.0
  - 5.2.1
  - 5.3.0
  - 5.4.0
  - 5.4.1
  - 5.5.0
  - 5.5.1
  - 5.5.2
  - 5.6.0
  - 5.7.0
  - 5.7.1
  - 5.7.2
  - 5.8.0
  - 5.9.0
references:
- type: WEB
  url: https://github.com/miguelgrinberg/python-socketio/security/advisories/GHSA-g8c6-8fjj-2r4m
- type: ADVISORY
  url: https://nvd.nist.gov/vuln/detail/CVE-2025-61765
- type: WEB
  url: https://github.com/miguelgrinberg/python-socketio/commit/53f6be094257ed81476b0e212c8cddd6d06ca39a
- type: PACKAGE
  url: https://github.com/miguelgrinberg/python-socketio
- type: WEB
  url: https://www.bluerock.io/post/cve-2025-61765-bluerock-discovers-critical-rce-in-socket-io-ecosystem
- type: PACKAGE
  url: https://pypi.org/project/python-socketio
- type: ADVISORY
  url: https://github.com/advisories/GHSA-g8c6-8fjj-2r4m
severity:
- type: CVSS_V3
  score: CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L