CVE-2026-48804

python-socketio is a Python implementation of the Socket.IO realtime client and server. The python-socketio server stores binary `EVENT` and `ACK` messages in memory while it waits to receive their binary attachments. Once all the attachments are received, these messages are then processed. Prior to version 5.16.4, an attacker can submit a binary message and intentionally omit sending one or more of its attachments to cause the message along with the partial list of received attachments to stay in memory for a long time. Version 5.16.4 takes the following measures to address this issue: Binary packets are only accepted from authenticated clients and, when a client disconnects, the server checks if there is a partial binary message being held for the client and deletes it.

• CWE-770

• https://github.com/miguelgrinberg/python-socketio/commit/4bec3ef87bcfd6ab5b94cd3ac09d873283a6960e
• https://github.com/miguelgrinberg/python-socketio/security/advisories/GHSA-5w7q-77mv-v69f

Published

Aug 11, 2026

Last Modified

Sep 10, 2026

Status

Awaiting Analysis

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-48798SSH.NET is a Secure Shell (SSH) library for .NET. In 2025.1.…7.1
• CVE-2026-48799Postiz is an AI social media scheduling tool. Prior to 2.21.…7.7
• CVE-2026-4880The Barcode Scanner (+Mobile App) – Inventory manager, Order…9.8
• CVE-2026-48800Notepad++ is a free and open-source source code editor. Prio…7.8
• CVE-2026-48801linkify-it is a links recognition library with full Unicode …7.5
• CVE-2026-48802python-engineio is a Python implementation of the Engine.IO …7.5
• CVE-2026-48805Twig is a template language for PHP. Prior to 3.27.0, deprec…9.1
• CVE-2026-48806Twig is a template language for PHP. Prior to 3.27.0, ArrayE…9.1
• CVE-2026-48807Twig is a template language for PHP. Prior to 3.27.0, the sa…9.1
• CVE-2026-48808Twig is a template language for PHP. Prior to 3.27.0, the co…7.5
• CVE-2026-48809python-engineio is a Python implementation of the Engine.IO …7.5
• CVE-2026-4881In affected versions of Octopus Server, permissions were not…6.5