CVE-2026-85078 — sanic chunked trailer request smuggling allows hidden second request execution
Sanic is an opensource python web server/framework. In version 25.12.0, Sanic's core HTTP/1.1 chunked-body handling does not fully consume the trailer-part after the terminating…
Published: 2026-09-17 · CVSS: 6.5 · CVSS 3.1
Sanic is an opensource python web server/framework. In version 25.12.0, Sanic's core HTTP/1.1 chunked-body handling does not fully consume the trailer-part after the terminating zero chunk before reusing the keep-alive connection buffer. A remote unauthenticated client can place attacker-controlled bytes in that trailer region, causing Sanic to parse and route them as a hidden second request after the outer request. This breaks HTTP request-boundary integrity and can provide a request-smuggling primitive when Sanic is deployed behind intermediaries. This issue is fixed in version 25.12.1.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7