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CVE-2026-48804

CVE-2026-48804 · python-socketio: Binary attachment accumulation can cause denial of service

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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.

CVSS 7.5 · High · EPSS 0.5% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • python-socketio

    Versions
    • < 5.16.4: Affected

    No fix published

  • python-socketio Debian:12

    Versions
    • 5.11.2-1
    • 5.11.2-1.1
    • 5.12.1-1
    • 5.13.0-1
    • 5.16.0-1
    • 5.17.0-1
    • 5.7.2-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-socketio Debian:13

    Versions
    • 5.12.1-1
    • 5.13.0-1
    • 5.16.0-1
    • 5.17.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-socketio Debian:14

    Versions
    • 5.12.1-1
    • 5.13.0-1
    • 5.16.0-1
    Affected ranges
    • ECOSYSTEM: < 5.17.0-1

    Update to 5.17.0-1

  • python-socketio PyPI

    Versions
    • 0.1.0
    • 0.2.0
    • 0.3.0
    • 0.4.0
    • 0.4.1
    • 0.4.2
    • 0.5.0
    • 0.5.1
    • 0.5.2
    • 0.6.0
    • 0.6.1
    • 0.7.0
    • 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
    • 5.14.0
    • 5.14.1
    • 5.14.2
    • 5.14.3
    • 5.15.0
    • 5.15.1
    • 5.16.0
    • 5.16.1
    • 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
    Affected ranges
    • ECOSYSTEM: < 5.16.2

    Update to 5.16.2

  • python-socketio Ubuntu:20.04:LTS

    Versions
    • 4.4.0-1
    • 4.4.0-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-socketio Ubuntu:22.04:LTS

    Versions
    • 5.0.3-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-socketio Ubuntu:24.04:LTS

    Versions
    • 5.7.2-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-socketio Ubuntu:26.10

    Versions
    • 5.16.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-socketio Ubuntu:26.04:LTS

    Versions
    • 5.13.0-1
    • 5.16.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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