CVE-2026-116579
Autobahn Python is a WebSocket and WAMP implementation for Python that supports Twisted and asyncio
- Risk score
- 45/100
- CVSS
- 5.9 v3.1
- Published
- 26 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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 infl…
- Affected
- See advisory
- Fix
- Upgrade the product to 26.10.1 or later.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 5.9 medium
- On your watchlist: python
References
- https://github.com/crossbario/autobahn-python/commit/a41442bbee4f6126a8ce1bb892840124c24d16f1
- https://github.com/crossbario/autobahn-python/pull/1987
- https://github.com/crossbario/autobahn-python/releases/tag/v26_10_1
- https://github.com/crossbario/autobahn-python/security/advisories/GHSA-pjh6-c8mg-3x7m
Original 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.
Last activity 26 Oct 2026. Patch Forecast updates every hour.