Intel

AIKIDO-2026-191135

matrix-synapse is vulnerable to Uncontrolled Resource Consumption

Uncontrolled Resource ConsumptionGHSA-6wjm-9p2x-gvpm Published 3 days ago

75

High Risk

This Affects:

PYTHONmatrix-synapse
0.0.1 - 1.157.1
Fixed in 1.157.2
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TL;DR

Synapse's existing mitigation against malicious multipart/form-data requests performs a case-sensitive check on the Content-Type header. By varying the case of the header, a client can bypass the mitigation. A crafted request then causes Synapse to rapidly exhaust all available memory and become unresponsive or be terminated, denying service to other users. The fix makes the content-type check case-insensitive.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range.

Background info

matrix-synapse is vulnerable to Uncontrolled Resource Consumption in versions 0.0.1 - 1.157.1.

How to fix this

Upgrade the matrix-synapse library to the patch version.