CVE-2026-116579
5.9
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploitability: 2.2 / Impact: 3.6
Source: security-advisories@github.com (Secondary)
Description
Autobahn Python is a WebSocket and WAMP implementation for Python that supports Twisted and asyncio. From 26.7.1 until 26.10.1, PerMessageBrotli.decompress_message_data in compress_brotli.py calls the Brotli decompressor without an output limit and checks maxMessagePayloadSize only after a complete frame has been inflated. An unauthenticated WebSocket client can send a small, highly compressed frame that allocates hundreds of MiB before rejection, causing memory-exhaustion denial of service on servers that enable the opt-in permessage-brotli feature through the compress extra. Deflate and bzip2 already enforce the remaining output budget and are outside this residual vulnerability. This issue is fixed in version 26.10.1.
Related CWEs
CWE-409
Improper Handling of Highly Compressed Data (Data Amplification)
The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.
CWE-770
Allocation of Resources Without Limits or Throttling
The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.
References (4)
Source: security-advisories@github.com
Source: security-advisories@github.com
Source: security-advisories@github.com
Source: security-advisories@github.com
Timeline
No history available yet.