CVE-2026-85078

medium

Description

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.

References

https://github.com/sanic-org/sanic/security/advisories/GHSA-wmj6-g64g-j7q5

https://github.com/sanic-org/sanic/releases/tag/v25.12.1

https://github.com/sanic-org/sanic/releases/tag/v24.12.1

https://github.com/sanic-org/sanic/pull/3165

https://github.com/sanic-org/sanic/pull/3164

https://github.com/sanic-org/sanic/commit/a332796506c7c588b6930b02a8886e43eb8ea8d6

https://github.com/sanic-org/sanic/commit/69a10d3b06babaa9e5f6d1af577364e9e53b6dea

https://github.com/sanic-org/sanic/commit/47349d689d65fa1907977ac100e867894aeafb22

Details

Source: Mitre, NVD

Published: 2026-09-17

Updated: 2026-09-17

Risk Information

CVSS v2

Base Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:P

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

Severity: Medium

EPSS

EPSS: 0.00296