miguelgrinberg python-engineio up to 4.13.1 denial of service

Summaryinfo

A vulnerability labeled as problematic has been found in miguelgrinberg python-engineio up to 4.13.1. Impacted is an unknown function. Executing a manipulation can lead to denial of service. This vulnerability is handled as CVE-2026-48802. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in miguelgrinberg python-engineio up to 4.13.1 and classified as problematic. This vulnerability affects an unknown part. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. CVE summarizes:

python-engineio is a Python implementation of the Engine.IO realtime client and server. Prior to version 4.13.2, an attacker can cause the creation of unnecessary background threads in the python-engineio server by exploiting the heartbeat mechanism, which launches a thread when a new connection is received, and when the client sends a PONG packet. This issue primarily affects synchronous servers. Asynchronous servers allocate background tasks instead of physical threads, which are lightweight and less likely to cause denial of service. However, the fix that was implemented was also applied to the asynchronous case. Version 4.13.2 addresses this issue as follows: The initial background thread (or async task( for heartbeat management is only launched if a client passes authentication in the `connect` handler; and the server now ensures that there is only one background heatbeat thread (or async task) per client at a given point in time. Out of sequence PONG packets are now discarded when an active heartbeat thread is already running.

The advisory is available at github.com. This vulnerability was named CVE-2026-48802 since 05/22/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading to version 4.13.2 eliminates this vulnerability.

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Productinfo

Type

• Programming Language Software

Vendor

• miguelgrinberg

Name

• python-engineio

Version

• 4.13.0
• 4.13.1

Website

• Product: https://github.com/miguelgrinberg/python-engineio/

CPE 2.3info

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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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