Skip to content
OpenAdvisories
High · 8.2 CVE-2026-85077 EUVD-2026-81626

Sanic: HTTP response header injection via missing CR/LF validation in Sanic HTTP/1.1 responses

Published Sep 17, 2026 · Updated Sep 21, 2026 · Assigned by GitHub_M

Description

Sanic is an opensource python web server/framework. Prior to version 24.12.1, and in version 25.12.0, the HTTP/1.1 response pipeline in sanic/response/types.py serializes response header names and values without rejecting carriage-return or line-feed characters. Applications that place attacker-controlled data in response.headers, file(..., filename=...), or cookie path and domain attributes can therefore emit injected headers and may split responses. Depending on application and proxy behavior, this can enable session fixation through injected cookies, cache poisoning, or security-header corruption. This issue is fixed in versions 24.12.1 and 25.12.1.

Affected products

VendorProductAffectedFixed
sanic-org sanic < 24.12.1, >= 25.12.0, < 25.12.1 —

References