# CVE-2026-48804: python-socketio: python-socketio is a Python implementation of the Socket.IO realtime client and server

CVE-2026-48804 is fixed in 2 products on 1 platform, first by SUSE-SU-2026:3086-1, released July 16, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-48804
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0049
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 16, 2026

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | python-python-socketio sles 15.6 | 5.7.2-150600.3.6.1 | [SUSE-SU-2026:3086-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-3086-1.md) | Jul 16, 2026 |
| Linux | python-python-socketio sles 15.7 | 5.7.2-150600.3.6.1 | [SUSE-SU-2026:3086-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-3086-1.md) | Jul 16, 2026 |
| Linux | python-socketio Debian 14 | 5.17.0-1 | [DEBIAN-CVE-2026-48804](https://patchblox.com/security/data/fix/linux/debian-cve-2026-48804.md) | Aug 11, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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