HTTP Response Splitting Affecting sanic package, versions [,24.12.1)[25.3.0,25.12.1)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-PYTHON-SANIC-20046660
- published22 Sept 2026
- disclosed17 Sept 2026
- creditDedal0, zulloper, sergeykochanov
Introduced: 17 Sep 2026
NewCVE-2026-85077 (opens in a new tab)How to fix?
Upgrade sanic to version 24.12.1, 25.12.1 or higher.
Overview
Affected versions of this package are vulnerable to HTTP Response Splitting via the HTTP/1.1 request parsing logic in sanic/http/http1.py, where malformed or conflicting transfer-encoding and content-length headers allow an attacker to inject a smuggled request into the processing pipeline. This can result in partial confidentiality loss and high-impact integrity violations against backend request handling.